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47686178 | 1 | /* $OpenBSD: session.c,v 1.233 2008/03/26 21:28:14 djm Exp $ */ |
3c0ef626 | 2 | /* |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
5 | * | |
6 | * As far as I am concerned, the code I have written for this software | |
7 | * can be used freely for any purpose. Any derived versions of this | |
8 | * software must be clearly marked as such, and if the derived work is | |
9 | * incompatible with the protocol description in the RFC file, it must be | |
10 | * called by a name other than "ssh" or "Secure Shell". | |
11 | * | |
12 | * SSH2 support by Markus Friedl. | |
13 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
14 | * | |
15 | * Redistribution and use in source and binary forms, with or without | |
16 | * modification, are permitted provided that the following conditions | |
17 | * are met: | |
18 | * 1. Redistributions of source code must retain the above copyright | |
19 | * notice, this list of conditions and the following disclaimer. | |
20 | * 2. Redistributions in binary form must reproduce the above copyright | |
21 | * notice, this list of conditions and the following disclaimer in the | |
22 | * documentation and/or other materials provided with the distribution. | |
23 | * | |
24 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
25 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
26 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
27 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
28 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
29 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
30 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
31 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
32 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
33 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
34 | */ | |
35 | ||
36 | #include "includes.h" | |
3c0ef626 | 37 | |
9108f8d9 | 38 | #include <sys/types.h> |
39 | #include <sys/param.h> | |
40 | #ifdef HAVE_SYS_STAT_H | |
41 | # include <sys/stat.h> | |
42 | #endif | |
43 | #include <sys/socket.h> | |
44 | #include <sys/un.h> | |
45 | #include <sys/wait.h> | |
46 | ||
47 | #include <arpa/inet.h> | |
48 | ||
49 | #include <errno.h> | |
50 | #include <grp.h> | |
51 | #ifdef HAVE_PATHS_H | |
52 | #include <paths.h> | |
53 | #endif | |
54 | #include <pwd.h> | |
55 | #include <signal.h> | |
56 | #include <stdarg.h> | |
57 | #include <stdio.h> | |
58 | #include <stdlib.h> | |
59 | #include <string.h> | |
60 | #include <unistd.h> | |
61 | ||
62 | #include "xmalloc.h" | |
3c0ef626 | 63 | #include "ssh.h" |
64 | #include "ssh1.h" | |
65 | #include "ssh2.h" | |
3c0ef626 | 66 | #include "sshpty.h" |
67 | #include "packet.h" | |
68 | #include "buffer.h" | |
c9f39d2c | 69 | #include "match.h" |
3c0ef626 | 70 | #include "uidswap.h" |
71 | #include "compat.h" | |
72 | #include "channels.h" | |
9108f8d9 | 73 | #include "key.h" |
74 | #include "cipher.h" | |
75 | #ifdef GSSAPI | |
76 | #include "ssh-gss.h" | |
77 | #endif | |
78 | #include "hostfile.h" | |
3c0ef626 | 79 | #include "auth.h" |
80 | #include "auth-options.h" | |
81 | #include "pathnames.h" | |
82 | #include "log.h" | |
83 | #include "servconf.h" | |
84 | #include "sshlogin.h" | |
85 | #include "serverloop.h" | |
86 | #include "canohost.h" | |
47686178 | 87 | #include "misc.h" |
3c0ef626 | 88 | #include "session.h" |
665a873d | 89 | #include "kex.h" |
700318f3 | 90 | #include "monitor_wrap.h" |
47686178 | 91 | #include "sftp.h" |
3c0ef626 | 92 | |
cdd66111 | 93 | #if defined(KRB5) && defined(USE_AFS) |
94 | #include <kafs.h> | |
95 | #endif | |
96 | ||
3c0ef626 | 97 | /* func */ |
98 | ||
99 | Session *session_new(void); | |
100 | void session_set_fds(Session *, int, int, int); | |
cdd66111 | 101 | void session_pty_cleanup(Session *); |
3c0ef626 | 102 | void session_proctitle(Session *); |
103 | int session_setup_x11fwd(Session *); | |
104 | void do_exec_pty(Session *, const char *); | |
105 | void do_exec_no_pty(Session *, const char *); | |
106 | void do_exec(Session *, const char *); | |
107 | void do_login(Session *, const char *); | |
108 | #ifdef LOGIN_NEEDS_UTMPX | |
109 | static void do_pre_login(Session *s); | |
110 | #endif | |
111 | void do_child(Session *, const char *); | |
112 | void do_motd(void); | |
113 | int check_quietlogin(Session *, const char *); | |
114 | ||
115 | static void do_authenticated1(Authctxt *); | |
116 | static void do_authenticated2(Authctxt *); | |
117 | ||
3c0ef626 | 118 | static int session_pty_req(Session *); |
119 | ||
120 | /* import */ | |
121 | extern ServerOptions options; | |
122 | extern char *__progname; | |
123 | extern int log_stderr; | |
124 | extern int debug_flag; | |
125 | extern u_int utmp_len; | |
126 | extern int startup_pipe; | |
127 | extern void destroy_sensitive_data(void); | |
0fff78ff | 128 | extern Buffer loginmsg; |
3c0ef626 | 129 | |
130 | /* original command from peer. */ | |
131 | const char *original_command = NULL; | |
132 | ||
133 | /* data */ | |
47686178 | 134 | #define MAX_SESSIONS 20 |
3c0ef626 | 135 | Session sessions[MAX_SESSIONS]; |
136 | ||
47686178 | 137 | #define SUBSYSTEM_NONE 0 |
138 | #define SUBSYSTEM_EXT 1 | |
139 | #define SUBSYSTEM_INT_SFTP 2 | |
140 | ||
3c0ef626 | 141 | #ifdef HAVE_LOGIN_CAP |
700318f3 | 142 | login_cap_t *lc; |
3c0ef626 | 143 | #endif |
144 | ||
cdd66111 | 145 | static int is_child = 0; |
146 | ||
f5799ae1 | 147 | /* Name and directory of socket for authentication agent forwarding. */ |
148 | static char *auth_sock_name = NULL; | |
149 | static char *auth_sock_dir = NULL; | |
150 | ||
151 | /* removes the agent forwarding socket */ | |
152 | ||
153 | static void | |
cdd66111 | 154 | auth_sock_cleanup_proc(struct passwd *pw) |
f5799ae1 | 155 | { |
f5799ae1 | 156 | if (auth_sock_name != NULL) { |
157 | temporarily_use_uid(pw); | |
158 | unlink(auth_sock_name); | |
159 | rmdir(auth_sock_dir); | |
160 | auth_sock_name = NULL; | |
161 | restore_uid(); | |
162 | } | |
163 | } | |
164 | ||
165 | static int | |
166 | auth_input_request_forwarding(struct passwd * pw) | |
167 | { | |
168 | Channel *nc; | |
169 | int sock; | |
170 | struct sockaddr_un sunaddr; | |
171 | ||
172 | if (auth_sock_name != NULL) { | |
173 | error("authentication forwarding requested twice."); | |
174 | return 0; | |
175 | } | |
176 | ||
177 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
178 | temporarily_use_uid(pw); | |
179 | ||
180 | /* Allocate a buffer for the socket name, and format the name. */ | |
181 | auth_sock_name = xmalloc(MAXPATHLEN); | |
182 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
cdd66111 | 183 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); |
f5799ae1 | 184 | |
185 | /* Create private directory for socket */ | |
186 | if (mkdtemp(auth_sock_dir) == NULL) { | |
187 | packet_send_debug("Agent forwarding disabled: " | |
188 | "mkdtemp() failed: %.100s", strerror(errno)); | |
189 | restore_uid(); | |
190 | xfree(auth_sock_name); | |
191 | xfree(auth_sock_dir); | |
192 | auth_sock_name = NULL; | |
193 | auth_sock_dir = NULL; | |
194 | return 0; | |
195 | } | |
196 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", | |
197 | auth_sock_dir, (long) getpid()); | |
198 | ||
f5799ae1 | 199 | /* Create the socket. */ |
200 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
201 | if (sock < 0) | |
202 | packet_disconnect("socket: %.100s", strerror(errno)); | |
203 | ||
204 | /* Bind it to the name. */ | |
205 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
206 | sunaddr.sun_family = AF_UNIX; | |
207 | strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); | |
208 | ||
9108f8d9 | 209 | if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) |
f5799ae1 | 210 | packet_disconnect("bind: %.100s", strerror(errno)); |
211 | ||
212 | /* Restore the privileged uid. */ | |
213 | restore_uid(); | |
214 | ||
215 | /* Start listening on the socket. */ | |
cdd66111 | 216 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) |
f5799ae1 | 217 | packet_disconnect("listen: %.100s", strerror(errno)); |
218 | ||
219 | /* Allocate a channel for the authentication agent socket. */ | |
220 | nc = channel_new("auth socket", | |
221 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
222 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
0fff78ff | 223 | 0, "auth socket", 1); |
f5799ae1 | 224 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
225 | return 1; | |
226 | } | |
227 | ||
cdd66111 | 228 | static void |
229 | display_loginmsg(void) | |
230 | { | |
665a873d | 231 | if (buffer_len(&loginmsg) > 0) { |
232 | buffer_append(&loginmsg, "\0", 1); | |
233 | printf("%s", (char *)buffer_ptr(&loginmsg)); | |
234 | buffer_clear(&loginmsg); | |
235 | } | |
cdd66111 | 236 | } |
f5799ae1 | 237 | |
3c0ef626 | 238 | void |
239 | do_authenticated(Authctxt *authctxt) | |
240 | { | |
6a9b3198 | 241 | setproctitle("%s", authctxt->pw->pw_name); |
242 | ||
3c0ef626 | 243 | /* setup the channel layer */ |
244 | if (!no_port_forwarding_flag && options.allow_tcp_forwarding) | |
245 | channel_permit_all_opens(); | |
246 | ||
247 | if (compat20) | |
248 | do_authenticated2(authctxt); | |
249 | else | |
250 | do_authenticated1(authctxt); | |
251 | ||
cdd66111 | 252 | do_cleanup(authctxt); |
3c0ef626 | 253 | } |
254 | ||
255 | /* | |
256 | * Prepares for an interactive session. This is called after the user has | |
257 | * been successfully authenticated. During this message exchange, pseudo | |
258 | * terminals are allocated, X11, TCP/IP, and authentication agent forwardings | |
259 | * are requested, etc. | |
260 | */ | |
261 | static void | |
262 | do_authenticated1(Authctxt *authctxt) | |
263 | { | |
264 | Session *s; | |
265 | char *command; | |
e9a17296 | 266 | int success, type, screen_flag; |
680cee3b | 267 | int enable_compression_after_reply = 0; |
268 | u_int proto_len, data_len, dlen, compression_level = 0; | |
3c0ef626 | 269 | |
270 | s = session_new(); | |
996d5e62 | 271 | if (s == NULL) { |
272 | error("no more sessions"); | |
273 | return; | |
274 | } | |
3c0ef626 | 275 | s->authctxt = authctxt; |
276 | s->pw = authctxt->pw; | |
277 | ||
278 | /* | |
279 | * We stay in this loop until the client requests to execute a shell | |
280 | * or a command. | |
281 | */ | |
282 | for (;;) { | |
283 | success = 0; | |
284 | ||
285 | /* Get a packet from the client. */ | |
e9a17296 | 286 | type = packet_read(); |
3c0ef626 | 287 | |
288 | /* Process the packet. */ | |
289 | switch (type) { | |
290 | case SSH_CMSG_REQUEST_COMPRESSION: | |
3c0ef626 | 291 | compression_level = packet_get_int(); |
e9a17296 | 292 | packet_check_eom(); |
3c0ef626 | 293 | if (compression_level < 1 || compression_level > 9) { |
c9f39d2c | 294 | packet_send_debug("Received invalid compression level %d.", |
e9a17296 | 295 | compression_level); |
3c0ef626 | 296 | break; |
297 | } | |
665a873d | 298 | if (options.compression == COMP_NONE) { |
f5799ae1 | 299 | debug2("compression disabled"); |
300 | break; | |
301 | } | |
3c0ef626 | 302 | /* Enable compression after we have responded with SUCCESS. */ |
303 | enable_compression_after_reply = 1; | |
304 | success = 1; | |
305 | break; | |
306 | ||
307 | case SSH_CMSG_REQUEST_PTY: | |
308 | success = session_pty_req(s); | |
309 | break; | |
310 | ||
311 | case SSH_CMSG_X11_REQUEST_FORWARDING: | |
312 | s->auth_proto = packet_get_string(&proto_len); | |
313 | s->auth_data = packet_get_string(&data_len); | |
314 | ||
315 | screen_flag = packet_get_protocol_flags() & | |
316 | SSH_PROTOFLAG_SCREEN_NUMBER; | |
317 | debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); | |
318 | ||
319 | if (packet_remaining() == 4) { | |
320 | if (!screen_flag) | |
321 | debug2("Buggy client: " | |
322 | "X11 screen flag missing"); | |
323 | s->screen = packet_get_int(); | |
324 | } else { | |
325 | s->screen = 0; | |
326 | } | |
e9a17296 | 327 | packet_check_eom(); |
3c0ef626 | 328 | success = session_setup_x11fwd(s); |
329 | if (!success) { | |
330 | xfree(s->auth_proto); | |
331 | xfree(s->auth_data); | |
332 | s->auth_proto = NULL; | |
333 | s->auth_data = NULL; | |
334 | } | |
335 | break; | |
336 | ||
337 | case SSH_CMSG_AGENT_REQUEST_FORWARDING: | |
338 | if (no_agent_forwarding_flag || compat13) { | |
339 | debug("Authentication agent forwarding not permitted for this authentication."); | |
340 | break; | |
341 | } | |
342 | debug("Received authentication agent forwarding request."); | |
343 | success = auth_input_request_forwarding(s->pw); | |
344 | break; | |
345 | ||
346 | case SSH_CMSG_PORT_FORWARD_REQUEST: | |
347 | if (no_port_forwarding_flag) { | |
348 | debug("Port forwarding not permitted for this authentication."); | |
349 | break; | |
350 | } | |
351 | if (!options.allow_tcp_forwarding) { | |
352 | debug("Port forwarding not permitted."); | |
353 | break; | |
354 | } | |
355 | debug("Received TCP/IP port forwarding request."); | |
9108f8d9 | 356 | if (channel_input_port_forward_request(s->pw->pw_uid == 0, |
357 | options.gateway_ports) < 0) { | |
358 | debug("Port forwarding failed."); | |
359 | break; | |
360 | } | |
3c0ef626 | 361 | success = 1; |
362 | break; | |
363 | ||
364 | case SSH_CMSG_MAX_PACKET_SIZE: | |
365 | if (packet_set_maxsize(packet_get_int()) > 0) | |
366 | success = 1; | |
367 | break; | |
e9a17296 | 368 | |
3c0ef626 | 369 | case SSH_CMSG_EXEC_SHELL: |
370 | case SSH_CMSG_EXEC_CMD: | |
371 | if (type == SSH_CMSG_EXEC_CMD) { | |
372 | command = packet_get_string(&dlen); | |
373 | debug("Exec command '%.500s'", command); | |
374 | do_exec(s, command); | |
375 | xfree(command); | |
376 | } else { | |
377 | do_exec(s, NULL); | |
378 | } | |
e9a17296 | 379 | packet_check_eom(); |
3c0ef626 | 380 | session_close(s); |
381 | return; | |
382 | ||
383 | default: | |
384 | /* | |
385 | * Any unknown messages in this phase are ignored, | |
386 | * and a failure message is returned. | |
387 | */ | |
0fff78ff | 388 | logit("Unknown packet type received after authentication: %d", type); |
3c0ef626 | 389 | } |
390 | packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE); | |
391 | packet_send(); | |
392 | packet_write_wait(); | |
393 | ||
394 | /* Enable compression now that we have replied if appropriate. */ | |
395 | if (enable_compression_after_reply) { | |
396 | enable_compression_after_reply = 0; | |
397 | packet_start_compression(compression_level); | |
398 | } | |
399 | } | |
400 | } | |
401 | ||
402 | /* | |
403 | * This is called to fork and execute a command when we have no tty. This | |
404 | * will call do_child from the child, and server_loop from the parent after | |
405 | * setting up file descriptors and such. | |
406 | */ | |
407 | void | |
408 | do_exec_no_pty(Session *s, const char *command) | |
409 | { | |
f5799ae1 | 410 | pid_t pid; |
3c0ef626 | 411 | |
412 | #ifdef USE_PIPES | |
413 | int pin[2], pout[2], perr[2]; | |
414 | /* Allocate pipes for communicating with the program. */ | |
415 | if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0) | |
416 | packet_disconnect("Could not create pipes: %.100s", | |
417 | strerror(errno)); | |
418 | #else /* USE_PIPES */ | |
419 | int inout[2], err[2]; | |
420 | /* Uses socket pairs to communicate with the program. */ | |
421 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 || | |
422 | socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) | |
423 | packet_disconnect("Could not create socket pairs: %.100s", | |
424 | strerror(errno)); | |
425 | #endif /* USE_PIPES */ | |
426 | if (s == NULL) | |
427 | fatal("do_exec_no_pty: no session"); | |
428 | ||
429 | session_proctitle(s); | |
430 | ||
3c0ef626 | 431 | /* Fork the child. */ |
432 | if ((pid = fork()) == 0) { | |
cdd66111 | 433 | is_child = 1; |
41b2f314 | 434 | |
3c0ef626 | 435 | /* Child. Reinitialize the log since the pid has changed. */ |
436 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
437 | ||
438 | /* | |
439 | * Create a new session and process group since the 4.4BSD | |
440 | * setlogin() affects the entire process group. | |
441 | */ | |
442 | if (setsid() < 0) | |
443 | error("setsid failed: %.100s", strerror(errno)); | |
444 | ||
445 | #ifdef USE_PIPES | |
446 | /* | |
447 | * Redirect stdin. We close the parent side of the socket | |
448 | * pair, and make the child side the standard input. | |
449 | */ | |
450 | close(pin[1]); | |
451 | if (dup2(pin[0], 0) < 0) | |
452 | perror("dup2 stdin"); | |
453 | close(pin[0]); | |
454 | ||
455 | /* Redirect stdout. */ | |
456 | close(pout[0]); | |
457 | if (dup2(pout[1], 1) < 0) | |
458 | perror("dup2 stdout"); | |
459 | close(pout[1]); | |
460 | ||
461 | /* Redirect stderr. */ | |
462 | close(perr[0]); | |
463 | if (dup2(perr[1], 2) < 0) | |
464 | perror("dup2 stderr"); | |
465 | close(perr[1]); | |
466 | #else /* USE_PIPES */ | |
467 | /* | |
468 | * Redirect stdin, stdout, and stderr. Stdin and stdout will | |
469 | * use the same socket, as some programs (particularly rdist) | |
470 | * seem to depend on it. | |
471 | */ | |
472 | close(inout[1]); | |
473 | close(err[1]); | |
474 | if (dup2(inout[0], 0) < 0) /* stdin */ | |
475 | perror("dup2 stdin"); | |
476 | if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */ | |
477 | perror("dup2 stdout"); | |
478 | if (dup2(err[0], 2) < 0) /* stderr */ | |
479 | perror("dup2 stderr"); | |
480 | #endif /* USE_PIPES */ | |
481 | ||
41b2f314 | 482 | #ifdef _UNICOS |
483 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
484 | #endif | |
485 | ||
3c0ef626 | 486 | /* Do processing for the child (exec command etc). */ |
487 | do_child(s, command); | |
488 | /* NOTREACHED */ | |
489 | } | |
41b2f314 | 490 | #ifdef _UNICOS |
491 | signal(WJSIGNAL, cray_job_termination_handler); | |
492 | #endif /* _UNICOS */ | |
3c0ef626 | 493 | #ifdef HAVE_CYGWIN |
494 | if (is_winnt) | |
495 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
496 | #endif | |
497 | if (pid < 0) | |
498 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
499 | s->pid = pid; | |
500 | /* Set interactive/non-interactive mode. */ | |
501 | packet_set_interactive(s->display != NULL); | |
502 | #ifdef USE_PIPES | |
503 | /* We are the parent. Close the child sides of the pipes. */ | |
504 | close(pin[0]); | |
505 | close(pout[1]); | |
506 | close(perr[1]); | |
507 | ||
508 | if (compat20) { | |
c9f39d2c | 509 | if (s->is_subsystem) { |
510 | close(perr[0]); | |
511 | perr[0] = -1; | |
512 | } | |
513 | session_set_fds(s, pin[1], pout[0], perr[0]); | |
3c0ef626 | 514 | } else { |
515 | /* Enter the interactive session. */ | |
516 | server_loop(pid, pin[1], pout[0], perr[0]); | |
517 | /* server_loop has closed pin[1], pout[0], and perr[0]. */ | |
518 | } | |
519 | #else /* USE_PIPES */ | |
520 | /* We are the parent. Close the child sides of the socket pairs. */ | |
521 | close(inout[0]); | |
522 | close(err[0]); | |
523 | ||
99be0775 | 524 | /* |
525 | * Clear loginmsg, since it's the child's responsibility to display | |
526 | * it to the user, otherwise multiple sessions may accumulate | |
527 | * multiple copies of the login messages. | |
528 | */ | |
529 | buffer_clear(&loginmsg); | |
530 | ||
3c0ef626 | 531 | /* |
532 | * Enter the interactive session. Note: server_loop must be able to | |
533 | * handle the case that fdin and fdout are the same. | |
534 | */ | |
535 | if (compat20) { | |
536 | session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); | |
537 | } else { | |
538 | server_loop(pid, inout[1], inout[1], err[1]); | |
539 | /* server_loop has closed inout[1] and err[1]. */ | |
540 | } | |
541 | #endif /* USE_PIPES */ | |
542 | } | |
543 | ||
544 | /* | |
545 | * This is called to fork and execute a command when we have a tty. This | |
546 | * will call do_child from the child, and server_loop from the parent after | |
547 | * setting up file descriptors, controlling tty, updating wtmp, utmp, | |
548 | * lastlog, and other such operations. | |
549 | */ | |
550 | void | |
551 | do_exec_pty(Session *s, const char *command) | |
552 | { | |
553 | int fdout, ptyfd, ttyfd, ptymaster; | |
554 | pid_t pid; | |
555 | ||
556 | if (s == NULL) | |
557 | fatal("do_exec_pty: no session"); | |
558 | ptyfd = s->ptyfd; | |
559 | ttyfd = s->ttyfd; | |
560 | ||
3c0ef626 | 561 | /* Fork the child. */ |
562 | if ((pid = fork()) == 0) { | |
cdd66111 | 563 | is_child = 1; |
3c0ef626 | 564 | |
565 | /* Child. Reinitialize the log because the pid has changed. */ | |
566 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
567 | /* Close the master side of the pseudo tty. */ | |
568 | close(ptyfd); | |
569 | ||
570 | /* Make the pseudo tty our controlling tty. */ | |
571 | pty_make_controlling_tty(&ttyfd, s->tty); | |
572 | ||
573 | /* Redirect stdin/stdout/stderr from the pseudo tty. */ | |
574 | if (dup2(ttyfd, 0) < 0) | |
575 | error("dup2 stdin: %s", strerror(errno)); | |
576 | if (dup2(ttyfd, 1) < 0) | |
577 | error("dup2 stdout: %s", strerror(errno)); | |
578 | if (dup2(ttyfd, 2) < 0) | |
579 | error("dup2 stderr: %s", strerror(errno)); | |
580 | ||
581 | /* Close the extra descriptor for the pseudo tty. */ | |
582 | close(ttyfd); | |
583 | ||
584 | /* record login, etc. similar to login(1) */ | |
585 | #ifndef HAVE_OSF_SIA | |
41b2f314 | 586 | if (!(options.use_login && command == NULL)) { |
587 | #ifdef _UNICOS | |
588 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
589 | #endif /* _UNICOS */ | |
3c0ef626 | 590 | do_login(s, command); |
41b2f314 | 591 | } |
3c0ef626 | 592 | # ifdef LOGIN_NEEDS_UTMPX |
593 | else | |
594 | do_pre_login(s); | |
595 | # endif | |
596 | #endif | |
597 | ||
598 | /* Do common processing for the child, such as execing the command. */ | |
599 | do_child(s, command); | |
600 | /* NOTREACHED */ | |
601 | } | |
41b2f314 | 602 | #ifdef _UNICOS |
603 | signal(WJSIGNAL, cray_job_termination_handler); | |
604 | #endif /* _UNICOS */ | |
3c0ef626 | 605 | #ifdef HAVE_CYGWIN |
606 | if (is_winnt) | |
607 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
608 | #endif | |
609 | if (pid < 0) | |
610 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
611 | s->pid = pid; | |
612 | ||
613 | /* Parent. Close the slave side of the pseudo tty. */ | |
614 | close(ttyfd); | |
615 | ||
616 | /* | |
617 | * Create another descriptor of the pty master side for use as the | |
618 | * standard input. We could use the original descriptor, but this | |
619 | * simplifies code in server_loop. The descriptor is bidirectional. | |
620 | */ | |
621 | fdout = dup(ptyfd); | |
622 | if (fdout < 0) | |
623 | packet_disconnect("dup #1 failed: %.100s", strerror(errno)); | |
624 | ||
625 | /* we keep a reference to the pty master */ | |
626 | ptymaster = dup(ptyfd); | |
627 | if (ptymaster < 0) | |
628 | packet_disconnect("dup #2 failed: %.100s", strerror(errno)); | |
629 | s->ptymaster = ptymaster; | |
630 | ||
631 | /* Enter interactive session. */ | |
632 | packet_set_interactive(1); | |
633 | if (compat20) { | |
634 | session_set_fds(s, ptyfd, fdout, -1); | |
635 | } else { | |
636 | server_loop(pid, ptyfd, fdout, -1); | |
637 | /* server_loop _has_ closed ptyfd and fdout. */ | |
638 | } | |
639 | } | |
640 | ||
641 | #ifdef LOGIN_NEEDS_UTMPX | |
642 | static void | |
643 | do_pre_login(Session *s) | |
644 | { | |
645 | socklen_t fromlen; | |
646 | struct sockaddr_storage from; | |
647 | pid_t pid = getpid(); | |
648 | ||
649 | /* | |
650 | * Get IP address of client. If the connection is not a socket, let | |
651 | * the address be 0.0.0.0. | |
652 | */ | |
653 | memset(&from, 0, sizeof(from)); | |
41b2f314 | 654 | fromlen = sizeof(from); |
3c0ef626 | 655 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 656 | if (getpeername(packet_get_connection_in(), |
9108f8d9 | 657 | (struct sockaddr *)&from, &fromlen) < 0) { |
3c0ef626 | 658 | debug("getpeername: %.100s", strerror(errno)); |
cdd66111 | 659 | cleanup_exit(255); |
3c0ef626 | 660 | } |
661 | } | |
662 | ||
663 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
0fff78ff | 664 | get_remote_name_or_ip(utmp_len, options.use_dns), |
6a9b3198 | 665 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 666 | } |
667 | #endif | |
668 | ||
669 | /* | |
670 | * This is called to fork and execute a command. If another command is | |
671 | * to be forced, execute that instead. | |
672 | */ | |
673 | void | |
674 | do_exec(Session *s, const char *command) | |
675 | { | |
9108f8d9 | 676 | if (options.adm_forced_command) { |
677 | original_command = command; | |
678 | command = options.adm_forced_command; | |
47686178 | 679 | if (strcmp(INTERNAL_SFTP_NAME, command) == 0) |
680 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
681 | else if (s->is_subsystem) | |
682 | s->is_subsystem = SUBSYSTEM_EXT; | |
9108f8d9 | 683 | debug("Forced command (config) '%.900s'", command); |
684 | } else if (forced_command) { | |
3c0ef626 | 685 | original_command = command; |
686 | command = forced_command; | |
47686178 | 687 | if (strcmp(INTERNAL_SFTP_NAME, command) == 0) |
688 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
689 | else if (s->is_subsystem) | |
690 | s->is_subsystem = SUBSYSTEM_EXT; | |
9108f8d9 | 691 | debug("Forced command (key option) '%.900s'", command); |
3c0ef626 | 692 | } |
693 | ||
996d5e62 | 694 | #ifdef SSH_AUDIT_EVENTS |
695 | if (command != NULL) | |
696 | PRIVSEP(audit_run_command(command)); | |
697 | else if (s->ttyfd == -1) { | |
698 | char *shell = s->pw->pw_shell; | |
699 | ||
700 | if (shell[0] == '\0') /* empty shell means /bin/sh */ | |
701 | shell =_PATH_BSHELL; | |
702 | PRIVSEP(audit_run_command(shell)); | |
0fff78ff | 703 | } |
704 | #endif | |
3c0ef626 | 705 | if (s->ttyfd != -1) |
706 | do_exec_pty(s, command); | |
707 | else | |
708 | do_exec_no_pty(s, command); | |
709 | ||
710 | original_command = NULL; | |
3c0ef626 | 711 | |
c9f39d2c | 712 | /* |
713 | * Clear loginmsg: it's the child's responsibility to display | |
714 | * it to the user, otherwise multiple sessions may accumulate | |
715 | * multiple copies of the login messages. | |
716 | */ | |
717 | buffer_clear(&loginmsg); | |
718 | } | |
e9a17296 | 719 | |
3c0ef626 | 720 | /* administrative, login(1)-like work */ |
721 | void | |
722 | do_login(Session *s, const char *command) | |
723 | { | |
3c0ef626 | 724 | socklen_t fromlen; |
725 | struct sockaddr_storage from; | |
3c0ef626 | 726 | struct passwd * pw = s->pw; |
727 | pid_t pid = getpid(); | |
728 | ||
729 | /* | |
730 | * Get IP address of client. If the connection is not a socket, let | |
731 | * the address be 0.0.0.0. | |
732 | */ | |
733 | memset(&from, 0, sizeof(from)); | |
6a9b3198 | 734 | fromlen = sizeof(from); |
3c0ef626 | 735 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 736 | if (getpeername(packet_get_connection_in(), |
e9a17296 | 737 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 738 | debug("getpeername: %.100s", strerror(errno)); |
cdd66111 | 739 | cleanup_exit(255); |
3c0ef626 | 740 | } |
741 | } | |
742 | ||
3c0ef626 | 743 | /* Record that there was a login on that tty from the remote host. */ |
700318f3 | 744 | if (!use_privsep) |
745 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
746 | get_remote_name_or_ip(utmp_len, | |
0fff78ff | 747 | options.use_dns), |
41b2f314 | 748 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 749 | |
750 | #ifdef USE_PAM | |
751 | /* | |
752 | * If password change is needed, do it now. | |
753 | * This needs to occur before the ~/.hushlogin check. | |
754 | */ | |
cdd66111 | 755 | if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) { |
756 | display_loginmsg(); | |
3c0ef626 | 757 | do_pam_chauthtok(); |
cdd66111 | 758 | s->authctxt->force_pwchange = 0; |
0fff78ff | 759 | /* XXX - signal [net] parent to enable forwardings */ |
3c0ef626 | 760 | } |
761 | #endif | |
762 | ||
763 | if (check_quietlogin(s, command)) | |
764 | return; | |
765 | ||
cdd66111 | 766 | display_loginmsg(); |
3c0ef626 | 767 | |
3c0ef626 | 768 | do_motd(); |
769 | } | |
770 | ||
771 | /* | |
772 | * Display the message of the day. | |
773 | */ | |
774 | void | |
775 | do_motd(void) | |
776 | { | |
777 | FILE *f; | |
778 | char buf[256]; | |
779 | ||
780 | if (options.print_motd) { | |
781 | #ifdef HAVE_LOGIN_CAP | |
782 | f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", | |
783 | "/etc/motd"), "r"); | |
784 | #else | |
785 | f = fopen("/etc/motd", "r"); | |
786 | #endif | |
787 | if (f) { | |
788 | while (fgets(buf, sizeof(buf), f)) | |
789 | fputs(buf, stdout); | |
790 | fclose(f); | |
791 | } | |
792 | } | |
793 | } | |
794 | ||
795 | ||
796 | /* | |
797 | * Check for quiet login, either .hushlogin or command given. | |
798 | */ | |
799 | int | |
800 | check_quietlogin(Session *s, const char *command) | |
801 | { | |
802 | char buf[256]; | |
803 | struct passwd *pw = s->pw; | |
804 | struct stat st; | |
805 | ||
806 | /* Return 1 if .hushlogin exists or a command given. */ | |
807 | if (command != NULL) | |
808 | return 1; | |
809 | snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); | |
810 | #ifdef HAVE_LOGIN_CAP | |
811 | if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) | |
812 | return 1; | |
813 | #else | |
814 | if (stat(buf, &st) >= 0) | |
815 | return 1; | |
816 | #endif | |
817 | return 0; | |
818 | } | |
819 | ||
820 | /* | |
821 | * Sets the value of the given variable in the environment. If the variable | |
822 | * already exists, its value is overriden. | |
823 | */ | |
0fff78ff | 824 | void |
3c0ef626 | 825 | child_set_env(char ***envp, u_int *envsizep, const char *name, |
e9a17296 | 826 | const char *value) |
3c0ef626 | 827 | { |
3c0ef626 | 828 | char **env; |
acc3d05e | 829 | u_int envsize; |
830 | u_int i, namelen; | |
3c0ef626 | 831 | |
0fff78ff | 832 | /* |
833 | * If we're passed an uninitialized list, allocate a single null | |
834 | * entry before continuing. | |
835 | */ | |
836 | if (*envp == NULL && *envsizep == 0) { | |
837 | *envp = xmalloc(sizeof(char *)); | |
838 | *envp[0] = NULL; | |
839 | *envsizep = 1; | |
840 | } | |
841 | ||
3c0ef626 | 842 | /* |
843 | * Find the slot where the value should be stored. If the variable | |
844 | * already exists, we reuse the slot; otherwise we append a new slot | |
845 | * at the end of the array, expanding if necessary. | |
846 | */ | |
847 | env = *envp; | |
848 | namelen = strlen(name); | |
849 | for (i = 0; env[i]; i++) | |
850 | if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') | |
851 | break; | |
852 | if (env[i]) { | |
853 | /* Reuse the slot. */ | |
854 | xfree(env[i]); | |
855 | } else { | |
856 | /* New variable. Expand if necessary. */ | |
acc3d05e | 857 | envsize = *envsizep; |
858 | if (i >= envsize - 1) { | |
859 | if (envsize >= 1000) | |
860 | fatal("child_set_env: too many env vars"); | |
861 | envsize += 50; | |
9108f8d9 | 862 | env = (*envp) = xrealloc(env, envsize, sizeof(char *)); |
acc3d05e | 863 | *envsizep = envsize; |
3c0ef626 | 864 | } |
865 | /* Need to set the NULL pointer at end of array beyond the new slot. */ | |
866 | env[i + 1] = NULL; | |
867 | } | |
868 | ||
869 | /* Allocate space and format the variable in the appropriate slot. */ | |
870 | env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); | |
871 | snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); | |
872 | } | |
873 | ||
874 | /* | |
875 | * Reads environment variables from the given file and adds/overrides them | |
876 | * into the environment. If the file does not exist, this does nothing. | |
877 | * Otherwise, it must consist of empty lines, comments (line starts with '#') | |
878 | * and assignments of the form name=value. No other forms are allowed. | |
879 | */ | |
880 | static void | |
881 | read_environment_file(char ***env, u_int *envsize, | |
e9a17296 | 882 | const char *filename) |
3c0ef626 | 883 | { |
884 | FILE *f; | |
885 | char buf[4096]; | |
886 | char *cp, *value; | |
680cee3b | 887 | u_int lineno = 0; |
3c0ef626 | 888 | |
889 | f = fopen(filename, "r"); | |
890 | if (!f) | |
891 | return; | |
892 | ||
893 | while (fgets(buf, sizeof(buf), f)) { | |
680cee3b | 894 | if (++lineno > 1000) |
895 | fatal("Too many lines in environment file %s", filename); | |
3c0ef626 | 896 | for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) |
897 | ; | |
898 | if (!*cp || *cp == '#' || *cp == '\n') | |
899 | continue; | |
47686178 | 900 | |
901 | cp[strcspn(cp, "\n")] = '\0'; | |
902 | ||
3c0ef626 | 903 | value = strchr(cp, '='); |
904 | if (value == NULL) { | |
680cee3b | 905 | fprintf(stderr, "Bad line %u in %.100s\n", lineno, |
906 | filename); | |
3c0ef626 | 907 | continue; |
908 | } | |
909 | /* | |
910 | * Replace the equals sign by nul, and advance value to | |
911 | * the value string. | |
912 | */ | |
913 | *value = '\0'; | |
914 | value++; | |
915 | child_set_env(env, envsize, cp, value); | |
916 | } | |
917 | fclose(f); | |
918 | } | |
919 | ||
0fff78ff | 920 | #ifdef HAVE_ETC_DEFAULT_LOGIN |
921 | /* | |
922 | * Return named variable from specified environment, or NULL if not present. | |
923 | */ | |
924 | static char * | |
925 | child_get_env(char **env, const char *name) | |
926 | { | |
927 | int i; | |
928 | size_t len; | |
929 | ||
930 | len = strlen(name); | |
931 | for (i=0; env[i] != NULL; i++) | |
932 | if (strncmp(name, env[i], len) == 0 && env[i][len] == '=') | |
933 | return(env[i] + len + 1); | |
934 | return NULL; | |
935 | } | |
936 | ||
937 | /* | |
938 | * Read /etc/default/login. | |
939 | * We pick up the PATH (or SUPATH for root) and UMASK. | |
940 | */ | |
941 | static void | |
942 | read_etc_default_login(char ***env, u_int *envsize, uid_t uid) | |
943 | { | |
944 | char **tmpenv = NULL, *var; | |
acc3d05e | 945 | u_int i, tmpenvsize = 0; |
cdd66111 | 946 | u_long mask; |
0fff78ff | 947 | |
948 | /* | |
949 | * We don't want to copy the whole file to the child's environment, | |
950 | * so we use a temporary environment and copy the variables we're | |
951 | * interested in. | |
952 | */ | |
953 | read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login"); | |
954 | ||
acc3d05e | 955 | if (tmpenv == NULL) |
956 | return; | |
957 | ||
0fff78ff | 958 | if (uid == 0) |
959 | var = child_get_env(tmpenv, "SUPATH"); | |
960 | else | |
961 | var = child_get_env(tmpenv, "PATH"); | |
962 | if (var != NULL) | |
963 | child_set_env(env, envsize, "PATH", var); | |
cdd66111 | 964 | |
0fff78ff | 965 | if ((var = child_get_env(tmpenv, "UMASK")) != NULL) |
966 | if (sscanf(var, "%5lo", &mask) == 1) | |
cdd66111 | 967 | umask((mode_t)mask); |
968 | ||
0fff78ff | 969 | for (i = 0; tmpenv[i] != NULL; i++) |
970 | xfree(tmpenv[i]); | |
971 | xfree(tmpenv); | |
972 | } | |
973 | #endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
974 | ||
665a873d | 975 | void |
976 | copy_environment(char **source, char ***env, u_int *envsize) | |
3c0ef626 | 977 | { |
e9a17296 | 978 | char *var_name, *var_val; |
3c0ef626 | 979 | int i; |
980 | ||
e9a17296 | 981 | if (source == NULL) |
3c0ef626 | 982 | return; |
983 | ||
e9a17296 | 984 | for(i = 0; source[i] != NULL; i++) { |
985 | var_name = xstrdup(source[i]); | |
986 | if ((var_val = strstr(var_name, "=")) == NULL) { | |
987 | xfree(var_name); | |
3c0ef626 | 988 | continue; |
3c0ef626 | 989 | } |
e9a17296 | 990 | *var_val++ = '\0'; |
3c0ef626 | 991 | |
e9a17296 | 992 | debug3("Copy environment: %s=%s", var_name, var_val); |
993 | child_set_env(env, envsize, var_name, var_val); | |
cdd66111 | 994 | |
e9a17296 | 995 | xfree(var_name); |
3c0ef626 | 996 | } |
997 | } | |
3c0ef626 | 998 | |
e9a17296 | 999 | static char ** |
1000 | do_setup_env(Session *s, const char *shell) | |
3c0ef626 | 1001 | { |
3c0ef626 | 1002 | char buf[256]; |
e9a17296 | 1003 | u_int i, envsize; |
9108f8d9 | 1004 | char **env, *laddr; |
e9a17296 | 1005 | struct passwd *pw = s->pw; |
9108f8d9 | 1006 | #ifndef HAVE_LOGIN_CAP |
1007 | char *path = NULL; | |
1008 | #endif | |
3c0ef626 | 1009 | |
1010 | /* Initialize the environment. */ | |
1011 | envsize = 100; | |
9108f8d9 | 1012 | env = xcalloc(envsize, sizeof(char *)); |
3c0ef626 | 1013 | env[0] = NULL; |
1014 | ||
1015 | #ifdef HAVE_CYGWIN | |
1016 | /* | |
1017 | * The Windows environment contains some setting which are | |
1018 | * important for a running system. They must not be dropped. | |
1019 | */ | |
996d5e62 | 1020 | { |
1021 | char **p; | |
1022 | ||
1023 | p = fetch_windows_environment(); | |
1024 | copy_environment(p, &env, &envsize); | |
1025 | free_windows_environment(p); | |
1026 | } | |
3c0ef626 | 1027 | #endif |
1028 | ||
0fff78ff | 1029 | #ifdef GSSAPI |
cdd66111 | 1030 | /* Allow any GSSAPI methods that we've used to alter |
0fff78ff | 1031 | * the childs environment as they see fit |
1032 | */ | |
1033 | ssh_gssapi_do_child(&env, &envsize); | |
1034 | #endif | |
1035 | ||
3c0ef626 | 1036 | if (!options.use_login) { |
1037 | /* Set basic environment. */ | |
c9f39d2c | 1038 | for (i = 0; i < s->num_env; i++) |
1039 | child_set_env(&env, &envsize, s->env[i].name, | |
1040 | s->env[i].val); | |
1041 | ||
3c0ef626 | 1042 | child_set_env(&env, &envsize, "USER", pw->pw_name); |
1043 | child_set_env(&env, &envsize, "LOGNAME", pw->pw_name); | |
6a9b3198 | 1044 | #ifdef _AIX |
1045 | child_set_env(&env, &envsize, "LOGIN", pw->pw_name); | |
1046 | #endif | |
3c0ef626 | 1047 | child_set_env(&env, &envsize, "HOME", pw->pw_dir); |
1048 | #ifdef HAVE_LOGIN_CAP | |
41b2f314 | 1049 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) |
1050 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); | |
1051 | else | |
1052 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
3c0ef626 | 1053 | #else /* HAVE_LOGIN_CAP */ |
1054 | # ifndef HAVE_CYGWIN | |
1055 | /* | |
1056 | * There's no standard path on Windows. The path contains | |
1057 | * important components pointing to the system directories, | |
1058 | * needed for loading shared libraries. So the path better | |
1059 | * remains intact here. | |
1060 | */ | |
0fff78ff | 1061 | # ifdef HAVE_ETC_DEFAULT_LOGIN |
1062 | read_etc_default_login(&env, &envsize, pw->pw_uid); | |
1063 | path = child_get_env(env, "PATH"); | |
1064 | # endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1065 | if (path == NULL || *path == '\0') { | |
cdd66111 | 1066 | child_set_env(&env, &envsize, "PATH", |
0fff78ff | 1067 | s->pw->pw_uid == 0 ? |
1068 | SUPERUSER_PATH : _PATH_STDPATH); | |
1069 | } | |
3c0ef626 | 1070 | # endif /* HAVE_CYGWIN */ |
1071 | #endif /* HAVE_LOGIN_CAP */ | |
1072 | ||
1073 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1074 | _PATH_MAILDIR, pw->pw_name); | |
1075 | child_set_env(&env, &envsize, "MAIL", buf); | |
1076 | ||
1077 | /* Normal systems set SHELL by default. */ | |
1078 | child_set_env(&env, &envsize, "SHELL", shell); | |
1079 | } | |
1080 | if (getenv("TZ")) | |
1081 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1082 | ||
1083 | /* Set custom environment options from RSA authentication. */ | |
1084 | if (!options.use_login) { | |
1085 | while (custom_environment) { | |
1086 | struct envstring *ce = custom_environment; | |
41b2f314 | 1087 | char *str = ce->s; |
e9a17296 | 1088 | |
41b2f314 | 1089 | for (i = 0; str[i] != '=' && str[i]; i++) |
3c0ef626 | 1090 | ; |
41b2f314 | 1091 | if (str[i] == '=') { |
1092 | str[i] = 0; | |
1093 | child_set_env(&env, &envsize, str, str + i + 1); | |
3c0ef626 | 1094 | } |
1095 | custom_environment = ce->next; | |
1096 | xfree(ce->s); | |
1097 | xfree(ce); | |
1098 | } | |
1099 | } | |
1100 | ||
41b2f314 | 1101 | /* SSH_CLIENT deprecated */ |
3c0ef626 | 1102 | snprintf(buf, sizeof buf, "%.50s %d %d", |
e9a17296 | 1103 | get_remote_ipaddr(), get_remote_port(), get_local_port()); |
3c0ef626 | 1104 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); |
1105 | ||
6a9b3198 | 1106 | laddr = get_local_ipaddr(packet_get_connection_in()); |
41b2f314 | 1107 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", |
6a9b3198 | 1108 | get_remote_ipaddr(), get_remote_port(), laddr, get_local_port()); |
1109 | xfree(laddr); | |
41b2f314 | 1110 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); |
1111 | ||
3c0ef626 | 1112 | if (s->ttyfd != -1) |
1113 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1114 | if (s->term) | |
1115 | child_set_env(&env, &envsize, "TERM", s->term); | |
1116 | if (s->display) | |
1117 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1118 | if (original_command) | |
1119 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1120 | original_command); | |
1121 | ||
41b2f314 | 1122 | #ifdef _UNICOS |
1123 | if (cray_tmpdir[0] != '\0') | |
1124 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1125 | #endif /* _UNICOS */ | |
1126 | ||
996d5e62 | 1127 | /* |
1128 | * Since we clear KRB5CCNAME at startup, if it's set now then it | |
1129 | * must have been set by a native authentication method (eg AIX or | |
1130 | * SIA), so copy it to the child. | |
1131 | */ | |
1132 | { | |
1133 | char *cp; | |
1134 | ||
1135 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1136 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1137 | } | |
1138 | ||
3c0ef626 | 1139 | #ifdef _AIX |
e9a17296 | 1140 | { |
1141 | char *cp; | |
1142 | ||
1143 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1144 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
e9a17296 | 1145 | read_environment_file(&env, &envsize, "/etc/environment"); |
1146 | } | |
3c0ef626 | 1147 | #endif |
3c0ef626 | 1148 | #ifdef KRB5 |
99be0775 | 1149 | if (s->authctxt->krb5_ccname) |
3c0ef626 | 1150 | child_set_env(&env, &envsize, "KRB5CCNAME", |
99be0775 | 1151 | s->authctxt->krb5_ccname); |
3c0ef626 | 1152 | #endif |
1153 | #ifdef USE_PAM | |
41b2f314 | 1154 | /* |
1155 | * Pull in any environment variables that may have | |
1156 | * been set by PAM. | |
1157 | */ | |
0fff78ff | 1158 | if (options.use_pam) { |
cdd66111 | 1159 | char **p; |
41b2f314 | 1160 | |
cdd66111 | 1161 | p = fetch_pam_child_environment(); |
1162 | copy_environment(p, &env, &envsize); | |
1163 | free_pam_environment(p); | |
1164 | ||
1165 | p = fetch_pam_environment(); | |
41b2f314 | 1166 | copy_environment(p, &env, &envsize); |
1167 | free_pam_environment(p); | |
1168 | } | |
3c0ef626 | 1169 | #endif /* USE_PAM */ |
1170 | ||
f5799ae1 | 1171 | if (auth_sock_name != NULL) |
3c0ef626 | 1172 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, |
f5799ae1 | 1173 | auth_sock_name); |
3c0ef626 | 1174 | |
1175 | /* read $HOME/.ssh/environment. */ | |
41b2f314 | 1176 | if (options.permit_user_env && !options.use_login) { |
3c0ef626 | 1177 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", |
41b2f314 | 1178 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); |
3c0ef626 | 1179 | read_environment_file(&env, &envsize, buf); |
1180 | } | |
1181 | if (debug_flag) { | |
1182 | /* dump the environment */ | |
1183 | fprintf(stderr, "Environment:\n"); | |
1184 | for (i = 0; env[i]; i++) | |
1185 | fprintf(stderr, " %.200s\n", env[i]); | |
1186 | } | |
e9a17296 | 1187 | return env; |
1188 | } | |
1189 | ||
1190 | /* | |
1191 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1192 | * first in this order). | |
1193 | */ | |
1194 | static void | |
1195 | do_rc_files(Session *s, const char *shell) | |
1196 | { | |
1197 | FILE *f = NULL; | |
1198 | char cmd[1024]; | |
1199 | int do_xauth; | |
1200 | struct stat st; | |
1201 | ||
1202 | do_xauth = | |
1203 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1204 | ||
47686178 | 1205 | /* ignore _PATH_SSH_USER_RC for subsystems and admin forced commands */ |
1206 | if (!s->is_subsystem && options.adm_forced_command == NULL && | |
1207 | !no_user_rc && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
e9a17296 | 1208 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", |
1209 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1210 | if (debug_flag) | |
1211 | fprintf(stderr, "Running %s\n", cmd); | |
1212 | f = popen(cmd, "w"); | |
1213 | if (f) { | |
1214 | if (do_xauth) | |
1215 | fprintf(f, "%s %s\n", s->auth_proto, | |
1216 | s->auth_data); | |
1217 | pclose(f); | |
1218 | } else | |
1219 | fprintf(stderr, "Could not run %s\n", | |
1220 | _PATH_SSH_USER_RC); | |
1221 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
1222 | if (debug_flag) | |
1223 | fprintf(stderr, "Running %s %s\n", _PATH_BSHELL, | |
1224 | _PATH_SSH_SYSTEM_RC); | |
1225 | f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w"); | |
1226 | if (f) { | |
1227 | if (do_xauth) | |
1228 | fprintf(f, "%s %s\n", s->auth_proto, | |
1229 | s->auth_data); | |
1230 | pclose(f); | |
1231 | } else | |
1232 | fprintf(stderr, "Could not run %s\n", | |
1233 | _PATH_SSH_SYSTEM_RC); | |
1234 | } else if (do_xauth && options.xauth_location != NULL) { | |
1235 | /* Add authority data to .Xauthority if appropriate. */ | |
1236 | if (debug_flag) { | |
1237 | fprintf(stderr, | |
6a9b3198 | 1238 | "Running %.500s remove %.100s\n", |
cdd66111 | 1239 | options.xauth_location, s->auth_display); |
6a9b3198 | 1240 | fprintf(stderr, |
1241 | "%.500s add %.100s %.100s %.100s\n", | |
e9a17296 | 1242 | options.xauth_location, s->auth_display, |
1243 | s->auth_proto, s->auth_data); | |
1244 | } | |
1245 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1246 | options.xauth_location); | |
1247 | f = popen(cmd, "w"); | |
1248 | if (f) { | |
6a9b3198 | 1249 | fprintf(f, "remove %s\n", |
1250 | s->auth_display); | |
e9a17296 | 1251 | fprintf(f, "add %s %s %s\n", |
1252 | s->auth_display, s->auth_proto, | |
1253 | s->auth_data); | |
1254 | pclose(f); | |
1255 | } else { | |
1256 | fprintf(stderr, "Could not run %s\n", | |
1257 | cmd); | |
1258 | } | |
1259 | } | |
1260 | } | |
1261 | ||
1262 | static void | |
1263 | do_nologin(struct passwd *pw) | |
1264 | { | |
1265 | FILE *f = NULL; | |
1266 | char buf[1024]; | |
1267 | ||
1268 | #ifdef HAVE_LOGIN_CAP | |
1269 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1270 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1271 | _PATH_NOLOGIN), "r"); | |
1272 | #else | |
1273 | if (pw->pw_uid) | |
1274 | f = fopen(_PATH_NOLOGIN, "r"); | |
1275 | #endif | |
1276 | if (f) { | |
1277 | /* /etc/nologin exists. Print its contents and exit. */ | |
0fff78ff | 1278 | logit("User %.100s not allowed because %s exists", |
41b2f314 | 1279 | pw->pw_name, _PATH_NOLOGIN); |
e9a17296 | 1280 | while (fgets(buf, sizeof(buf), f)) |
1281 | fputs(buf, stderr); | |
1282 | fclose(f); | |
6a9b3198 | 1283 | fflush(NULL); |
e9a17296 | 1284 | exit(254); |
1285 | } | |
1286 | } | |
1287 | ||
47686178 | 1288 | /* |
1289 | * Chroot into a directory after checking it for safety: all path components | |
1290 | * must be root-owned directories with strict permissions. | |
1291 | */ | |
1292 | static void | |
1293 | safely_chroot(const char *path, uid_t uid) | |
1294 | { | |
1295 | const char *cp; | |
1296 | char component[MAXPATHLEN]; | |
1297 | struct stat st; | |
1298 | ||
1299 | if (*path != '/') | |
1300 | fatal("chroot path does not begin at root"); | |
1301 | if (strlen(path) >= sizeof(component)) | |
1302 | fatal("chroot path too long"); | |
1303 | ||
1304 | /* | |
1305 | * Descend the path, checking that each component is a | |
1306 | * root-owned directory with strict permissions. | |
1307 | */ | |
1308 | for (cp = path; cp != NULL;) { | |
1309 | if ((cp = strchr(cp, '/')) == NULL) | |
1310 | strlcpy(component, path, sizeof(component)); | |
1311 | else { | |
1312 | cp++; | |
1313 | memcpy(component, path, cp - path); | |
1314 | component[cp - path] = '\0'; | |
1315 | } | |
1316 | ||
1317 | debug3("%s: checking '%s'", __func__, component); | |
1318 | ||
1319 | if (stat(component, &st) != 0) | |
1320 | fatal("%s: stat(\"%s\"): %s", __func__, | |
1321 | component, strerror(errno)); | |
1322 | if (st.st_uid != 0 || (st.st_mode & 022) != 0) | |
1323 | fatal("bad ownership or modes for chroot " | |
1324 | "directory %s\"%s\"", | |
1325 | cp == NULL ? "" : "component ", component); | |
1326 | if (!S_ISDIR(st.st_mode)) | |
1327 | fatal("chroot path %s\"%s\" is not a directory", | |
1328 | cp == NULL ? "" : "component ", component); | |
1329 | ||
1330 | } | |
1331 | ||
1332 | if (chdir(path) == -1) | |
1333 | fatal("Unable to chdir to chroot path \"%s\": " | |
1334 | "%s", path, strerror(errno)); | |
1335 | if (chroot(path) == -1) | |
1336 | fatal("chroot(\"%s\"): %s", path, strerror(errno)); | |
1337 | if (chdir("/") == -1) | |
1338 | fatal("%s: chdir(/) after chroot: %s", | |
1339 | __func__, strerror(errno)); | |
1340 | verbose("Changed root directory to \"%s\"", path); | |
1341 | } | |
1342 | ||
e9a17296 | 1343 | /* Set login name, uid, gid, and groups. */ |
700318f3 | 1344 | void |
e9a17296 | 1345 | do_setusercontext(struct passwd *pw) |
1346 | { | |
47686178 | 1347 | char *chroot_path, *tmp; |
1348 | ||
1349 | #ifdef WITH_SELINUX | |
1350 | /* Cache selinux status for later use */ | |
1351 | (void)ssh_selinux_enabled(); | |
1352 | #endif | |
1353 | ||
6a9b3198 | 1354 | #ifndef HAVE_CYGWIN |
1355 | if (getuid() == 0 || geteuid() == 0) | |
e9a17296 | 1356 | #endif /* HAVE_CYGWIN */ |
6a9b3198 | 1357 | { |
1358 | ||
f5799ae1 | 1359 | #ifdef HAVE_SETPCRED |
0fff78ff | 1360 | if (setpcred(pw->pw_name, (char **)NULL) == -1) |
1361 | fatal("Failed to set process credentials"); | |
f5799ae1 | 1362 | #endif /* HAVE_SETPCRED */ |
e9a17296 | 1363 | #ifdef HAVE_LOGIN_CAP |
41b2f314 | 1364 | # ifdef __bsdi__ |
680cee3b | 1365 | setpgid(0, 0); |
41b2f314 | 1366 | # endif |
cdd66111 | 1367 | # ifdef USE_PAM |
1368 | if (options.use_pam) { | |
d4487008 | 1369 | do_pam_setcred(use_privsep); |
cdd66111 | 1370 | } |
1371 | # endif /* USE_PAM */ | |
e9a17296 | 1372 | if (setusercontext(lc, pw, pw->pw_uid, |
47686178 | 1373 | (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETUSER))) < 0) { |
e9a17296 | 1374 | perror("unable to set user context"); |
1375 | exit(1); | |
1376 | } | |
1377 | #else | |
1378 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1379 | /* Sets login uid for accounting */ | |
1380 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1381 | error("setluid: %s", strerror(errno)); | |
1382 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1383 | ||
1384 | if (setlogin(pw->pw_name) < 0) | |
1385 | error("setlogin failed: %s", strerror(errno)); | |
1386 | if (setgid(pw->pw_gid) < 0) { | |
1387 | perror("setgid"); | |
1388 | exit(1); | |
1389 | } | |
1390 | /* Initialize the group list. */ | |
1391 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1392 | perror("initgroups"); | |
1393 | exit(1); | |
1394 | } | |
1395 | endgrent(); | |
1396 | # ifdef USE_PAM | |
1397 | /* | |
cdd66111 | 1398 | * PAM credentials may take the form of supplementary groups. |
e9a17296 | 1399 | * These will have been wiped by the above initgroups() call. |
1400 | * Reestablish them here. | |
1401 | */ | |
0fff78ff | 1402 | if (options.use_pam) { |
d4487008 | 1403 | do_pam_setcred(use_privsep); |
0fff78ff | 1404 | } |
e9a17296 | 1405 | # endif /* USE_PAM */ |
1406 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1407 | irix_setusercontext(pw); | |
47686178 | 1408 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ |
680cee3b | 1409 | # ifdef _AIX |
41b2f314 | 1410 | aix_usrinfo(pw); |
680cee3b | 1411 | # endif /* _AIX */ |
47686178 | 1412 | # ifdef USE_LIBIAF |
665a873d | 1413 | if (set_id(pw->pw_name) != 0) { |
1414 | exit(1); | |
1415 | } | |
47686178 | 1416 | # endif /* USE_LIBIAF */ |
1417 | #endif | |
1418 | ||
1419 | if (options.chroot_directory != NULL && | |
1420 | strcasecmp(options.chroot_directory, "none") != 0) { | |
1421 | tmp = tilde_expand_filename(options.chroot_directory, | |
1422 | pw->pw_uid); | |
1423 | chroot_path = percent_expand(tmp, "h", pw->pw_dir, | |
1424 | "u", pw->pw_name, (char *)NULL); | |
1425 | safely_chroot(chroot_path, pw->pw_uid); | |
1426 | free(tmp); | |
1427 | free(chroot_path); | |
1428 | } | |
1429 | ||
1430 | #ifdef HAVE_LOGIN_CAP | |
1431 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETUSER) < 0) { | |
1432 | perror("unable to set user context (setuser)"); | |
1433 | exit(1); | |
1434 | } | |
1435 | #else | |
e9a17296 | 1436 | /* Permanently switch to the desired uid. */ |
1437 | permanently_set_uid(pw); | |
1438 | #endif | |
1439 | } | |
6a9b3198 | 1440 | |
1441 | #ifdef HAVE_CYGWIN | |
1442 | if (is_winnt) | |
1443 | #endif | |
e9a17296 | 1444 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) |
1445 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
9108f8d9 | 1446 | |
1447 | #ifdef WITH_SELINUX | |
1448 | ssh_selinux_setup_exec_context(pw->pw_name); | |
1449 | #endif | |
e9a17296 | 1450 | } |
1451 | ||
cdd66111 | 1452 | static void |
1453 | do_pwchange(Session *s) | |
1454 | { | |
c9f39d2c | 1455 | fflush(NULL); |
cdd66111 | 1456 | fprintf(stderr, "WARNING: Your password has expired.\n"); |
1457 | if (s->ttyfd != -1) { | |
c9f39d2c | 1458 | fprintf(stderr, |
cdd66111 | 1459 | "You must change your password now and login again!\n"); |
996d5e62 | 1460 | #ifdef PASSWD_NEEDS_USERNAME |
1461 | execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name, | |
1462 | (char *)NULL); | |
1463 | #else | |
cdd66111 | 1464 | execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); |
996d5e62 | 1465 | #endif |
cdd66111 | 1466 | perror("passwd"); |
1467 | } else { | |
1468 | fprintf(stderr, | |
1469 | "Password change required but no TTY available.\n"); | |
1470 | } | |
1471 | exit(1); | |
1472 | } | |
1473 | ||
700318f3 | 1474 | static void |
1475 | launch_login(struct passwd *pw, const char *hostname) | |
1476 | { | |
1477 | /* Launch login(1). */ | |
1478 | ||
f5799ae1 | 1479 | execl(LOGIN_PROGRAM, "login", "-h", hostname, |
700318f3 | 1480 | #ifdef xxxLOGIN_NEEDS_TERM |
f5799ae1 | 1481 | (s->term ? s->term : "unknown"), |
700318f3 | 1482 | #endif /* LOGIN_NEEDS_TERM */ |
1483 | #ifdef LOGIN_NO_ENDOPT | |
1484 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1485 | #else | |
1486 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1487 | #endif | |
1488 | ||
1489 | /* Login couldn't be executed, die. */ | |
1490 | ||
1491 | perror("login"); | |
1492 | exit(1); | |
1493 | } | |
1494 | ||
cdd66111 | 1495 | static void |
1496 | child_close_fds(void) | |
1497 | { | |
1498 | int i; | |
1499 | ||
1500 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1501 | close(packet_get_connection_in()); | |
1502 | else { | |
1503 | close(packet_get_connection_in()); | |
1504 | close(packet_get_connection_out()); | |
1505 | } | |
1506 | /* | |
1507 | * Close all descriptors related to channels. They will still remain | |
1508 | * open in the parent. | |
1509 | */ | |
1510 | /* XXX better use close-on-exec? -markus */ | |
1511 | channel_close_all(); | |
1512 | ||
1513 | /* | |
1514 | * Close any extra file descriptors. Note that there may still be | |
1515 | * descriptors left by system functions. They will be closed later. | |
1516 | */ | |
1517 | endpwent(); | |
1518 | ||
1519 | /* | |
2c06c99b | 1520 | * Close any extra open file descriptors so that we don't have them |
cdd66111 | 1521 | * hanging around in clients. Note that we want to do this after |
1522 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1523 | * descriptors open. | |
1524 | */ | |
1525 | for (i = 3; i < 64; i++) | |
1526 | close(i); | |
1527 | } | |
1528 | ||
e9a17296 | 1529 | /* |
1530 | * Performs common processing for the child, such as setting up the | |
1531 | * environment, closing extra file descriptors, setting the user and group | |
1532 | * ids, and executing the command or shell. | |
1533 | */ | |
47686178 | 1534 | #define ARGV_MAX 10 |
e9a17296 | 1535 | void |
1536 | do_child(Session *s, const char *command) | |
1537 | { | |
1538 | extern char **environ; | |
1539 | char **env; | |
47686178 | 1540 | char *argv[ARGV_MAX]; |
e9a17296 | 1541 | const char *shell, *shell0, *hostname = NULL; |
1542 | struct passwd *pw = s->pw; | |
e9a17296 | 1543 | |
1544 | /* remove hostkey from the child's memory */ | |
1545 | destroy_sensitive_data(); | |
1546 | ||
cdd66111 | 1547 | /* Force a password change */ |
1548 | if (s->authctxt->force_pwchange) { | |
1549 | do_setusercontext(pw); | |
1550 | child_close_fds(); | |
1551 | do_pwchange(s); | |
1552 | exit(1); | |
1553 | } | |
1554 | ||
e9a17296 | 1555 | /* login(1) is only called if we execute the login shell */ |
1556 | if (options.use_login && command != NULL) | |
1557 | options.use_login = 0; | |
1558 | ||
41b2f314 | 1559 | #ifdef _UNICOS |
1560 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1561 | #endif /* _UNICOS */ | |
1562 | ||
e9a17296 | 1563 | /* |
1564 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1565 | * switch, so we let login(1) to this for us. | |
1566 | */ | |
1567 | if (!options.use_login) { | |
1568 | #ifdef HAVE_OSF_SIA | |
6a9b3198 | 1569 | session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty); |
e9a17296 | 1570 | if (!check_quietlogin(s, command)) |
1571 | do_motd(); | |
1572 | #else /* HAVE_OSF_SIA */ | |
2c06c99b | 1573 | /* When PAM is enabled we rely on it to do the nologin check */ |
1574 | if (!options.use_pam) | |
1575 | do_nologin(pw); | |
e9a17296 | 1576 | do_setusercontext(pw); |
c9f39d2c | 1577 | /* |
1578 | * PAM session modules in do_setusercontext may have | |
1579 | * generated messages, so if this in an interactive | |
1580 | * login then display them too. | |
1581 | */ | |
996d5e62 | 1582 | if (!check_quietlogin(s, command)) |
c9f39d2c | 1583 | display_loginmsg(); |
e9a17296 | 1584 | #endif /* HAVE_OSF_SIA */ |
1585 | } | |
1586 | ||
996d5e62 | 1587 | #ifdef USE_PAM |
dec6d9fe | 1588 | if (options.use_pam && !options.use_login && !is_pam_session_open()) { |
1589 | debug3("PAM session not opened, exiting"); | |
996d5e62 | 1590 | display_loginmsg(); |
1591 | exit(254); | |
1592 | } | |
1593 | #endif | |
1594 | ||
e9a17296 | 1595 | /* |
1596 | * Get the shell from the password data. An empty shell field is | |
1597 | * legal, and means /bin/sh. | |
1598 | */ | |
1599 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
6a9b3198 | 1600 | |
1601 | /* | |
1602 | * Make sure $SHELL points to the shell from the password file, | |
1603 | * even if shell is overridden from login.conf | |
1604 | */ | |
1605 | env = do_setup_env(s, shell); | |
1606 | ||
e9a17296 | 1607 | #ifdef HAVE_LOGIN_CAP |
1608 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1609 | #endif | |
1610 | ||
3c0ef626 | 1611 | /* we have to stash the hostname before we close our socket. */ |
1612 | if (options.use_login) | |
1613 | hostname = get_remote_name_or_ip(utmp_len, | |
0fff78ff | 1614 | options.use_dns); |
3c0ef626 | 1615 | /* |
1616 | * Close the connection descriptors; note that this is the child, and | |
1617 | * the server will still have the socket open, and it is important | |
1618 | * that we do not shutdown it. Note that the descriptors cannot be | |
1619 | * closed before building the environment, as we call | |
1620 | * get_remote_ipaddr there. | |
1621 | */ | |
cdd66111 | 1622 | child_close_fds(); |
3c0ef626 | 1623 | |
1624 | /* | |
cdd66111 | 1625 | * Must take new environment into use so that .ssh/rc, |
1626 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
3c0ef626 | 1627 | */ |
cdd66111 | 1628 | environ = env; |
3c0ef626 | 1629 | |
cdd66111 | 1630 | #if defined(KRB5) && defined(USE_AFS) |
3c0ef626 | 1631 | /* |
cdd66111 | 1632 | * At this point, we check to see if AFS is active and if we have |
1633 | * a valid Kerberos 5 TGT. If so, it seems like a good idea to see | |
1634 | * if we can (and need to) extend the ticket into an AFS token. If | |
1635 | * we don't do this, we run into potential problems if the user's | |
1636 | * home directory is in AFS and it's not world-readable. | |
3c0ef626 | 1637 | */ |
3c0ef626 | 1638 | |
cdd66111 | 1639 | if (options.kerberos_get_afs_token && k_hasafs() && |
665a873d | 1640 | (s->authctxt->krb5_ctx != NULL)) { |
cdd66111 | 1641 | char cell[64]; |
1642 | ||
1643 | debug("Getting AFS token"); | |
1644 | ||
1645 | k_setpag(); | |
1646 | ||
1647 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) | |
1648 | krb5_afslog(s->authctxt->krb5_ctx, | |
1649 | s->authctxt->krb5_fwd_ccache, cell, NULL); | |
1650 | ||
1651 | krb5_afslog_home(s->authctxt->krb5_ctx, | |
1652 | s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); | |
1653 | } | |
1654 | #endif | |
3c0ef626 | 1655 | |
2c06c99b | 1656 | /* Change current directory to the user's home directory. */ |
3c0ef626 | 1657 | if (chdir(pw->pw_dir) < 0) { |
1658 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1659 | pw->pw_dir, strerror(errno)); | |
1660 | #ifdef HAVE_LOGIN_CAP | |
1661 | if (login_getcapbool(lc, "requirehome", 0)) | |
1662 | exit(1); | |
1663 | #endif | |
1664 | } | |
1665 | ||
47686178 | 1666 | closefrom(STDERR_FILENO + 1); |
1667 | ||
e9a17296 | 1668 | if (!options.use_login) |
1669 | do_rc_files(s, shell); | |
3c0ef626 | 1670 | |
1671 | /* restore SIGPIPE for child */ | |
9108f8d9 | 1672 | signal(SIGPIPE, SIG_DFL); |
3c0ef626 | 1673 | |
47686178 | 1674 | if (s->is_subsystem == SUBSYSTEM_INT_SFTP) { |
1675 | extern int optind, optreset; | |
1676 | int i; | |
1677 | char *p, *args; | |
1678 | ||
1679 | setproctitle("%s@internal-sftp-server", s->pw->pw_name); | |
1680 | args = strdup(command ? command : "sftp-server"); | |
1681 | for (i = 0, (p = strtok(args, " ")); p; (p = strtok(NULL, " "))) | |
1682 | if (i < ARGV_MAX - 1) | |
1683 | argv[i++] = p; | |
1684 | argv[i] = NULL; | |
1685 | optind = optreset = 1; | |
1686 | __progname = argv[0]; | |
1687 | exit(sftp_server_main(i, argv, s->pw)); | |
1688 | } | |
1689 | ||
e9a17296 | 1690 | if (options.use_login) { |
700318f3 | 1691 | launch_login(pw, hostname); |
1692 | /* NEVERREACHED */ | |
e9a17296 | 1693 | } |
1694 | ||
1695 | /* Get the last component of the shell name. */ | |
1696 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1697 | shell0++; | |
1698 | else | |
1699 | shell0 = shell; | |
1700 | ||
3c0ef626 | 1701 | /* |
1702 | * If we have no command, execute the shell. In this case, the shell | |
1703 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1704 | * this is a login shell. | |
1705 | */ | |
1706 | if (!command) { | |
e9a17296 | 1707 | char argv0[256]; |
3c0ef626 | 1708 | |
e9a17296 | 1709 | /* Start the shell. Set initial character to '-'. */ |
1710 | argv0[0] = '-'; | |
3c0ef626 | 1711 | |
e9a17296 | 1712 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) |
1713 | >= sizeof(argv0) - 1) { | |
1714 | errno = EINVAL; | |
3c0ef626 | 1715 | perror(shell); |
1716 | exit(1); | |
e9a17296 | 1717 | } |
3c0ef626 | 1718 | |
e9a17296 | 1719 | /* Execute the shell. */ |
1720 | argv[0] = argv0; | |
1721 | argv[1] = NULL; | |
1722 | execve(shell, argv, env); | |
3c0ef626 | 1723 | |
e9a17296 | 1724 | /* Executing the shell failed. */ |
1725 | perror(shell); | |
1726 | exit(1); | |
3c0ef626 | 1727 | } |
1728 | /* | |
1729 | * Execute the command using the user's shell. This uses the -c | |
1730 | * option to execute the command. | |
1731 | */ | |
e9a17296 | 1732 | argv[0] = (char *) shell0; |
3c0ef626 | 1733 | argv[1] = "-c"; |
1734 | argv[2] = (char *) command; | |
1735 | argv[3] = NULL; | |
1736 | execve(shell, argv, env); | |
1737 | perror(shell); | |
1738 | exit(1); | |
1739 | } | |
1740 | ||
1741 | Session * | |
1742 | session_new(void) | |
1743 | { | |
1744 | int i; | |
1745 | static int did_init = 0; | |
1746 | if (!did_init) { | |
1747 | debug("session_new: init"); | |
e9a17296 | 1748 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1749 | sessions[i].used = 0; |
1750 | } | |
1751 | did_init = 1; | |
1752 | } | |
e9a17296 | 1753 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1754 | Session *s = &sessions[i]; |
1755 | if (! s->used) { | |
1756 | memset(s, 0, sizeof(*s)); | |
1757 | s->chanid = -1; | |
1758 | s->ptyfd = -1; | |
1759 | s->ttyfd = -1; | |
1760 | s->used = 1; | |
1761 | s->self = i; | |
665a873d | 1762 | s->x11_chanids = NULL; |
3c0ef626 | 1763 | debug("session_new: session %d", i); |
1764 | return s; | |
1765 | } | |
1766 | } | |
1767 | return NULL; | |
1768 | } | |
1769 | ||
1770 | static void | |
1771 | session_dump(void) | |
1772 | { | |
1773 | int i; | |
e9a17296 | 1774 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1775 | Session *s = &sessions[i]; |
f5799ae1 | 1776 | debug("dump: used %d session %d %p channel %d pid %ld", |
3c0ef626 | 1777 | s->used, |
1778 | s->self, | |
1779 | s, | |
1780 | s->chanid, | |
f5799ae1 | 1781 | (long)s->pid); |
3c0ef626 | 1782 | } |
1783 | } | |
1784 | ||
1785 | int | |
1786 | session_open(Authctxt *authctxt, int chanid) | |
1787 | { | |
1788 | Session *s = session_new(); | |
1789 | debug("session_open: channel %d", chanid); | |
1790 | if (s == NULL) { | |
1791 | error("no more sessions"); | |
1792 | return 0; | |
1793 | } | |
1794 | s->authctxt = authctxt; | |
1795 | s->pw = authctxt->pw; | |
cdd66111 | 1796 | if (s->pw == NULL || !authctxt->valid) |
3c0ef626 | 1797 | fatal("no user for session %d", s->self); |
1798 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1799 | s->chanid = chanid; | |
1800 | return 1; | |
1801 | } | |
1802 | ||
700318f3 | 1803 | Session * |
1804 | session_by_tty(char *tty) | |
1805 | { | |
1806 | int i; | |
1807 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1808 | Session *s = &sessions[i]; | |
1809 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1810 | debug("session_by_tty: session %d tty %s", i, tty); | |
1811 | return s; | |
1812 | } | |
1813 | } | |
1814 | debug("session_by_tty: unknown tty %.100s", tty); | |
1815 | session_dump(); | |
1816 | return NULL; | |
1817 | } | |
1818 | ||
3c0ef626 | 1819 | static Session * |
1820 | session_by_channel(int id) | |
1821 | { | |
1822 | int i; | |
e9a17296 | 1823 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1824 | Session *s = &sessions[i]; |
1825 | if (s->used && s->chanid == id) { | |
1826 | debug("session_by_channel: session %d channel %d", i, id); | |
1827 | return s; | |
1828 | } | |
1829 | } | |
1830 | debug("session_by_channel: unknown channel %d", id); | |
1831 | session_dump(); | |
1832 | return NULL; | |
1833 | } | |
1834 | ||
665a873d | 1835 | static Session * |
1836 | session_by_x11_channel(int id) | |
1837 | { | |
1838 | int i, j; | |
1839 | ||
1840 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1841 | Session *s = &sessions[i]; | |
1842 | ||
1843 | if (s->x11_chanids == NULL || !s->used) | |
1844 | continue; | |
1845 | for (j = 0; s->x11_chanids[j] != -1; j++) { | |
1846 | if (s->x11_chanids[j] == id) { | |
1847 | debug("session_by_x11_channel: session %d " | |
1848 | "channel %d", s->self, id); | |
1849 | return s; | |
1850 | } | |
1851 | } | |
1852 | } | |
1853 | debug("session_by_x11_channel: unknown channel %d", id); | |
1854 | session_dump(); | |
1855 | return NULL; | |
1856 | } | |
1857 | ||
3c0ef626 | 1858 | static Session * |
1859 | session_by_pid(pid_t pid) | |
1860 | { | |
1861 | int i; | |
f5799ae1 | 1862 | debug("session_by_pid: pid %ld", (long)pid); |
e9a17296 | 1863 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1864 | Session *s = &sessions[i]; |
1865 | if (s->used && s->pid == pid) | |
1866 | return s; | |
1867 | } | |
f5799ae1 | 1868 | error("session_by_pid: unknown pid %ld", (long)pid); |
3c0ef626 | 1869 | session_dump(); |
1870 | return NULL; | |
1871 | } | |
1872 | ||
1873 | static int | |
1874 | session_window_change_req(Session *s) | |
1875 | { | |
1876 | s->col = packet_get_int(); | |
1877 | s->row = packet_get_int(); | |
1878 | s->xpixel = packet_get_int(); | |
1879 | s->ypixel = packet_get_int(); | |
e9a17296 | 1880 | packet_check_eom(); |
3c0ef626 | 1881 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); |
1882 | return 1; | |
1883 | } | |
1884 | ||
1885 | static int | |
1886 | session_pty_req(Session *s) | |
1887 | { | |
1888 | u_int len; | |
1889 | int n_bytes; | |
1890 | ||
1891 | if (no_pty_flag) { | |
1892 | debug("Allocating a pty not permitted for this authentication."); | |
1893 | return 0; | |
1894 | } | |
1895 | if (s->ttyfd != -1) { | |
1896 | packet_disconnect("Protocol error: you already have a pty."); | |
1897 | return 0; | |
1898 | } | |
1899 | ||
1900 | s->term = packet_get_string(&len); | |
1901 | ||
1902 | if (compat20) { | |
1903 | s->col = packet_get_int(); | |
1904 | s->row = packet_get_int(); | |
1905 | } else { | |
1906 | s->row = packet_get_int(); | |
1907 | s->col = packet_get_int(); | |
1908 | } | |
1909 | s->xpixel = packet_get_int(); | |
1910 | s->ypixel = packet_get_int(); | |
1911 | ||
1912 | if (strcmp(s->term, "") == 0) { | |
1913 | xfree(s->term); | |
1914 | s->term = NULL; | |
1915 | } | |
1916 | ||
1917 | /* Allocate a pty and open it. */ | |
1918 | debug("Allocating pty."); | |
700318f3 | 1919 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { |
3c0ef626 | 1920 | if (s->term) |
1921 | xfree(s->term); | |
1922 | s->term = NULL; | |
1923 | s->ptyfd = -1; | |
1924 | s->ttyfd = -1; | |
1925 | error("session_pty_req: session %d alloc failed", s->self); | |
1926 | return 0; | |
1927 | } | |
1928 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
1929 | ||
1930 | /* for SSH1 the tty modes length is not given */ | |
1931 | if (!compat20) | |
1932 | n_bytes = packet_remaining(); | |
1933 | tty_parse_modes(s->ttyfd, &n_bytes); | |
1934 | ||
700318f3 | 1935 | if (!use_privsep) |
1936 | pty_setowner(s->pw, s->tty); | |
3c0ef626 | 1937 | |
1938 | /* Set window size from the packet. */ | |
1939 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
1940 | ||
e9a17296 | 1941 | packet_check_eom(); |
3c0ef626 | 1942 | session_proctitle(s); |
1943 | return 1; | |
1944 | } | |
1945 | ||
1946 | static int | |
1947 | session_subsystem_req(Session *s) | |
1948 | { | |
1949 | struct stat st; | |
1950 | u_int len; | |
1951 | int success = 0; | |
9108f8d9 | 1952 | char *prog, *cmd, *subsys = packet_get_string(&len); |
665a873d | 1953 | u_int i; |
3c0ef626 | 1954 | |
e9a17296 | 1955 | packet_check_eom(); |
0fff78ff | 1956 | logit("subsystem request for %.100s", subsys); |
3c0ef626 | 1957 | |
1958 | for (i = 0; i < options.num_subsystems; i++) { | |
1959 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
9108f8d9 | 1960 | prog = options.subsystem_command[i]; |
1961 | cmd = options.subsystem_args[i]; | |
47686178 | 1962 | if (!strcmp(INTERNAL_SFTP_NAME, prog)) { |
1963 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
1964 | } else if (stat(prog, &st) < 0) { | |
9108f8d9 | 1965 | error("subsystem: cannot stat %s: %s", prog, |
3c0ef626 | 1966 | strerror(errno)); |
1967 | break; | |
47686178 | 1968 | } else { |
1969 | s->is_subsystem = SUBSYSTEM_EXT; | |
3c0ef626 | 1970 | } |
1971 | debug("subsystem: exec() %s", cmd); | |
3c0ef626 | 1972 | do_exec(s, cmd); |
1973 | success = 1; | |
e9a17296 | 1974 | break; |
3c0ef626 | 1975 | } |
1976 | } | |
1977 | ||
1978 | if (!success) | |
0fff78ff | 1979 | logit("subsystem request for %.100s failed, subsystem not found", |
3c0ef626 | 1980 | subsys); |
1981 | ||
1982 | xfree(subsys); | |
1983 | return success; | |
1984 | } | |
1985 | ||
1986 | static int | |
1987 | session_x11_req(Session *s) | |
1988 | { | |
1989 | int success; | |
1990 | ||
665a873d | 1991 | if (s->auth_proto != NULL || s->auth_data != NULL) { |
1992 | error("session_x11_req: session %d: " | |
2c06c99b | 1993 | "x11 forwarding already active", s->self); |
665a873d | 1994 | return 0; |
1995 | } | |
3c0ef626 | 1996 | s->single_connection = packet_get_char(); |
1997 | s->auth_proto = packet_get_string(NULL); | |
1998 | s->auth_data = packet_get_string(NULL); | |
1999 | s->screen = packet_get_int(); | |
e9a17296 | 2000 | packet_check_eom(); |
3c0ef626 | 2001 | |
2002 | success = session_setup_x11fwd(s); | |
2003 | if (!success) { | |
2004 | xfree(s->auth_proto); | |
2005 | xfree(s->auth_data); | |
2006 | s->auth_proto = NULL; | |
2007 | s->auth_data = NULL; | |
2008 | } | |
2009 | return success; | |
2010 | } | |
2011 | ||
2012 | static int | |
2013 | session_shell_req(Session *s) | |
2014 | { | |
e9a17296 | 2015 | packet_check_eom(); |
3c0ef626 | 2016 | do_exec(s, NULL); |
2017 | return 1; | |
2018 | } | |
2019 | ||
2020 | static int | |
2021 | session_exec_req(Session *s) | |
2022 | { | |
2023 | u_int len; | |
2024 | char *command = packet_get_string(&len); | |
e9a17296 | 2025 | packet_check_eom(); |
3c0ef626 | 2026 | do_exec(s, command); |
2027 | xfree(command); | |
2028 | return 1; | |
2029 | } | |
2030 | ||
0fff78ff | 2031 | static int |
2032 | session_break_req(Session *s) | |
2033 | { | |
0fff78ff | 2034 | |
c9f39d2c | 2035 | packet_get_int(); /* ignored */ |
0fff78ff | 2036 | packet_check_eom(); |
2037 | ||
2038 | if (s->ttyfd == -1 || | |
2039 | tcsendbreak(s->ttyfd, 0) < 0) | |
2040 | return 0; | |
2041 | return 1; | |
2042 | } | |
2043 | ||
c9f39d2c | 2044 | static int |
2045 | session_env_req(Session *s) | |
2046 | { | |
2047 | char *name, *val; | |
2048 | u_int name_len, val_len, i; | |
2049 | ||
2050 | name = packet_get_string(&name_len); | |
2051 | val = packet_get_string(&val_len); | |
2052 | packet_check_eom(); | |
2053 | ||
2054 | /* Don't set too many environment variables */ | |
2055 | if (s->num_env > 128) { | |
2056 | debug2("Ignoring env request %s: too many env vars", name); | |
2057 | goto fail; | |
2058 | } | |
2059 | ||
2060 | for (i = 0; i < options.num_accept_env; i++) { | |
2061 | if (match_pattern(name, options.accept_env[i])) { | |
2062 | debug2("Setting env %d: %s=%s", s->num_env, name, val); | |
9108f8d9 | 2063 | s->env = xrealloc(s->env, s->num_env + 1, |
2064 | sizeof(*s->env)); | |
c9f39d2c | 2065 | s->env[s->num_env].name = name; |
2066 | s->env[s->num_env].val = val; | |
2067 | s->num_env++; | |
2068 | return (1); | |
2069 | } | |
2070 | } | |
2071 | debug2("Ignoring env request %s: disallowed name", name); | |
2072 | ||
2073 | fail: | |
2074 | xfree(name); | |
2075 | xfree(val); | |
2076 | return (0); | |
2077 | } | |
2078 | ||
3c0ef626 | 2079 | static int |
2080 | session_auth_agent_req(Session *s) | |
2081 | { | |
2082 | static int called = 0; | |
e9a17296 | 2083 | packet_check_eom(); |
3c0ef626 | 2084 | if (no_agent_forwarding_flag) { |
2085 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
2086 | return 0; | |
2087 | } | |
2088 | if (called) { | |
2089 | return 0; | |
2090 | } else { | |
2091 | called = 1; | |
2092 | return auth_input_request_forwarding(s->pw); | |
2093 | } | |
2094 | } | |
2095 | ||
e9a17296 | 2096 | int |
2097 | session_input_channel_req(Channel *c, const char *rtype) | |
3c0ef626 | 2098 | { |
3c0ef626 | 2099 | int success = 0; |
3c0ef626 | 2100 | Session *s; |
3c0ef626 | 2101 | |
e9a17296 | 2102 | if ((s = session_by_channel(c->self)) == NULL) { |
0fff78ff | 2103 | logit("session_input_channel_req: no session %d req %.100s", |
e9a17296 | 2104 | c->self, rtype); |
2105 | return 0; | |
2106 | } | |
2107 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
3c0ef626 | 2108 | |
2109 | /* | |
2110 | * a session is in LARVAL state until a shell, a command | |
2111 | * or a subsystem is executed | |
2112 | */ | |
2113 | if (c->type == SSH_CHANNEL_LARVAL) { | |
2114 | if (strcmp(rtype, "shell") == 0) { | |
2115 | success = session_shell_req(s); | |
2116 | } else if (strcmp(rtype, "exec") == 0) { | |
2117 | success = session_exec_req(s); | |
2118 | } else if (strcmp(rtype, "pty-req") == 0) { | |
799ae497 | 2119 | success = session_pty_req(s); |
3c0ef626 | 2120 | } else if (strcmp(rtype, "x11-req") == 0) { |
2121 | success = session_x11_req(s); | |
2122 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
2123 | success = session_auth_agent_req(s); | |
2124 | } else if (strcmp(rtype, "subsystem") == 0) { | |
2125 | success = session_subsystem_req(s); | |
c9f39d2c | 2126 | } else if (strcmp(rtype, "env") == 0) { |
2127 | success = session_env_req(s); | |
3c0ef626 | 2128 | } |
2129 | } | |
2130 | if (strcmp(rtype, "window-change") == 0) { | |
2131 | success = session_window_change_req(s); | |
c9f39d2c | 2132 | } else if (strcmp(rtype, "break") == 0) { |
2133 | success = session_break_req(s); | |
3c0ef626 | 2134 | } |
c9f39d2c | 2135 | |
e9a17296 | 2136 | return success; |
3c0ef626 | 2137 | } |
2138 | ||
2139 | void | |
2140 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
2141 | { | |
2142 | if (!compat20) | |
2143 | fatal("session_set_fds: called for proto != 2.0"); | |
2144 | /* | |
2145 | * now that have a child and a pipe to the child, | |
2146 | * we can activate our channel and register the fd's | |
2147 | */ | |
2148 | if (s->chanid == -1) | |
2149 | fatal("no channel for session %d", s->self); | |
2150 | channel_set_fds(s->chanid, | |
2151 | fdout, fdin, fderr, | |
2152 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
e9a17296 | 2153 | 1, |
2154 | CHAN_SES_WINDOW_DEFAULT); | |
3c0ef626 | 2155 | } |
2156 | ||
2157 | /* | |
2158 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
2159 | * (e.g., due to a dropped connection). | |
2160 | */ | |
700318f3 | 2161 | void |
cdd66111 | 2162 | session_pty_cleanup2(Session *s) |
3c0ef626 | 2163 | { |
3c0ef626 | 2164 | if (s == NULL) { |
2165 | error("session_pty_cleanup: no session"); | |
2166 | return; | |
2167 | } | |
2168 | if (s->ttyfd == -1) | |
2169 | return; | |
2170 | ||
2171 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
2172 | ||
2173 | /* Record that the user has logged out. */ | |
2174 | if (s->pid != 0) | |
e9a17296 | 2175 | record_logout(s->pid, s->tty, s->pw->pw_name); |
3c0ef626 | 2176 | |
2177 | /* Release the pseudo-tty. */ | |
700318f3 | 2178 | if (getuid() == 0) |
2179 | pty_release(s->tty); | |
3c0ef626 | 2180 | |
2181 | /* | |
2182 | * Close the server side of the socket pairs. We must do this after | |
2183 | * the pty cleanup, so that another process doesn't get this pty | |
2184 | * while we're still cleaning up. | |
2185 | */ | |
2186 | if (close(s->ptymaster) < 0) | |
700318f3 | 2187 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); |
3c0ef626 | 2188 | |
2189 | /* unlink pty from session */ | |
2190 | s->ttyfd = -1; | |
2191 | } | |
2192 | ||
700318f3 | 2193 | void |
cdd66111 | 2194 | session_pty_cleanup(Session *s) |
700318f3 | 2195 | { |
cdd66111 | 2196 | PRIVSEP(session_pty_cleanup2(s)); |
700318f3 | 2197 | } |
2198 | ||
41b2f314 | 2199 | static char * |
2200 | sig2name(int sig) | |
2201 | { | |
2202 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
2203 | SSH_SIG(ABRT); | |
2204 | SSH_SIG(ALRM); | |
2205 | SSH_SIG(FPE); | |
2206 | SSH_SIG(HUP); | |
2207 | SSH_SIG(ILL); | |
2208 | SSH_SIG(INT); | |
2209 | SSH_SIG(KILL); | |
2210 | SSH_SIG(PIPE); | |
2211 | SSH_SIG(QUIT); | |
2212 | SSH_SIG(SEGV); | |
2213 | SSH_SIG(TERM); | |
2214 | SSH_SIG(USR1); | |
2215 | SSH_SIG(USR2); | |
2216 | #undef SSH_SIG | |
2217 | return "SIG@openssh.com"; | |
2218 | } | |
2219 | ||
665a873d | 2220 | static void |
2221 | session_close_x11(int id) | |
2222 | { | |
2223 | Channel *c; | |
2224 | ||
2c06c99b | 2225 | if ((c = channel_by_id(id)) == NULL) { |
665a873d | 2226 | debug("session_close_x11: x11 channel %d missing", id); |
2227 | } else { | |
2228 | /* Detach X11 listener */ | |
2229 | debug("session_close_x11: detach x11 channel %d", id); | |
2230 | channel_cancel_cleanup(id); | |
2231 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2232 | chan_mark_dead(c); | |
2233 | } | |
2234 | } | |
2235 | ||
2236 | static void | |
2237 | session_close_single_x11(int id, void *arg) | |
2238 | { | |
2239 | Session *s; | |
2240 | u_int i; | |
2241 | ||
2242 | debug3("session_close_single_x11: channel %d", id); | |
2243 | channel_cancel_cleanup(id); | |
799ae497 | 2244 | if ((s = session_by_x11_channel(id)) == NULL) |
665a873d | 2245 | fatal("session_close_single_x11: no x11 channel %d", id); |
2246 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2247 | debug("session_close_single_x11: session %d: " | |
2248 | "closing channel %d", s->self, s->x11_chanids[i]); | |
2249 | /* | |
2250 | * The channel "id" is already closing, but make sure we | |
2251 | * close all of its siblings. | |
2252 | */ | |
2253 | if (s->x11_chanids[i] != id) | |
2254 | session_close_x11(s->x11_chanids[i]); | |
2255 | } | |
2256 | xfree(s->x11_chanids); | |
2257 | s->x11_chanids = NULL; | |
2258 | if (s->display) { | |
2259 | xfree(s->display); | |
2260 | s->display = NULL; | |
2261 | } | |
2262 | if (s->auth_proto) { | |
2263 | xfree(s->auth_proto); | |
2264 | s->auth_proto = NULL; | |
2265 | } | |
2266 | if (s->auth_data) { | |
2267 | xfree(s->auth_data); | |
2268 | s->auth_data = NULL; | |
2269 | } | |
2270 | if (s->auth_display) { | |
2271 | xfree(s->auth_display); | |
2272 | s->auth_display = NULL; | |
2273 | } | |
2274 | } | |
2275 | ||
3c0ef626 | 2276 | static void |
2277 | session_exit_message(Session *s, int status) | |
2278 | { | |
2279 | Channel *c; | |
e9a17296 | 2280 | |
2281 | if ((c = channel_lookup(s->chanid)) == NULL) | |
3c0ef626 | 2282 | fatal("session_exit_message: session %d: no channel %d", |
2283 | s->self, s->chanid); | |
f5799ae1 | 2284 | debug("session_exit_message: session %d channel %d pid %ld", |
2285 | s->self, s->chanid, (long)s->pid); | |
3c0ef626 | 2286 | |
2287 | if (WIFEXITED(status)) { | |
e9a17296 | 2288 | channel_request_start(s->chanid, "exit-status", 0); |
3c0ef626 | 2289 | packet_put_int(WEXITSTATUS(status)); |
2290 | packet_send(); | |
2291 | } else if (WIFSIGNALED(status)) { | |
e9a17296 | 2292 | channel_request_start(s->chanid, "exit-signal", 0); |
41b2f314 | 2293 | packet_put_cstring(sig2name(WTERMSIG(status))); |
3c0ef626 | 2294 | #ifdef WCOREDUMP |
47686178 | 2295 | packet_put_char(WCOREDUMP(status)? 1 : 0); |
3c0ef626 | 2296 | #else /* WCOREDUMP */ |
2297 | packet_put_char(0); | |
2298 | #endif /* WCOREDUMP */ | |
2299 | packet_put_cstring(""); | |
2300 | packet_put_cstring(""); | |
2301 | packet_send(); | |
2302 | } else { | |
2303 | /* Some weird exit cause. Just exit. */ | |
2304 | packet_disconnect("wait returned status %04x.", status); | |
2305 | } | |
2306 | ||
2307 | /* disconnect channel */ | |
2308 | debug("session_exit_message: release channel %d", s->chanid); | |
2c06c99b | 2309 | |
2310 | /* | |
2311 | * Adjust cleanup callback attachment to send close messages when | |
9108f8d9 | 2312 | * the channel gets EOF. The session will be then be closed |
2c06c99b | 2313 | * by session_close_by_channel when the childs close their fds. |
2314 | */ | |
2315 | channel_register_cleanup(c->self, session_close_by_channel, 1); | |
2316 | ||
3c0ef626 | 2317 | /* |
2318 | * emulate a write failure with 'chan_write_failed', nobody will be | |
2319 | * interested in data we write. | |
2320 | * Note that we must not call 'chan_read_failed', since there could | |
2321 | * be some more data waiting in the pipe. | |
2322 | */ | |
2323 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2324 | chan_write_failed(c); | |
3c0ef626 | 2325 | } |
2326 | ||
700318f3 | 2327 | void |
3c0ef626 | 2328 | session_close(Session *s) |
2329 | { | |
665a873d | 2330 | u_int i; |
c9f39d2c | 2331 | |
f5799ae1 | 2332 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
cdd66111 | 2333 | if (s->ttyfd != -1) |
3c0ef626 | 2334 | session_pty_cleanup(s); |
3c0ef626 | 2335 | if (s->term) |
2336 | xfree(s->term); | |
2337 | if (s->display) | |
2338 | xfree(s->display); | |
665a873d | 2339 | if (s->x11_chanids) |
2340 | xfree(s->x11_chanids); | |
e9a17296 | 2341 | if (s->auth_display) |
2342 | xfree(s->auth_display); | |
3c0ef626 | 2343 | if (s->auth_data) |
2344 | xfree(s->auth_data); | |
2345 | if (s->auth_proto) | |
2346 | xfree(s->auth_proto); | |
2347 | s->used = 0; | |
9108f8d9 | 2348 | if (s->env != NULL) { |
2349 | for (i = 0; i < s->num_env; i++) { | |
2350 | xfree(s->env[i].name); | |
2351 | xfree(s->env[i].val); | |
2352 | } | |
c9f39d2c | 2353 | xfree(s->env); |
9108f8d9 | 2354 | } |
3c0ef626 | 2355 | session_proctitle(s); |
2356 | } | |
2357 | ||
2358 | void | |
2359 | session_close_by_pid(pid_t pid, int status) | |
2360 | { | |
2361 | Session *s = session_by_pid(pid); | |
2362 | if (s == NULL) { | |
f5799ae1 | 2363 | debug("session_close_by_pid: no session for pid %ld", |
2364 | (long)pid); | |
3c0ef626 | 2365 | return; |
2366 | } | |
2367 | if (s->chanid != -1) | |
2368 | session_exit_message(s, status); | |
2c06c99b | 2369 | if (s->ttyfd != -1) |
2370 | session_pty_cleanup(s); | |
f2f068fa | 2371 | s->pid = 0; |
3c0ef626 | 2372 | } |
2373 | ||
2374 | /* | |
2375 | * this is called when a channel dies before | |
2376 | * the session 'child' itself dies | |
2377 | */ | |
2378 | void | |
2379 | session_close_by_channel(int id, void *arg) | |
2380 | { | |
2381 | Session *s = session_by_channel(id); | |
2c06c99b | 2382 | u_int i; |
665a873d | 2383 | |
3c0ef626 | 2384 | if (s == NULL) { |
2385 | debug("session_close_by_channel: no session for id %d", id); | |
2386 | return; | |
2387 | } | |
f5799ae1 | 2388 | debug("session_close_by_channel: channel %d child %ld", |
2389 | id, (long)s->pid); | |
3c0ef626 | 2390 | if (s->pid != 0) { |
2391 | debug("session_close_by_channel: channel %d: has child", id); | |
2392 | /* | |
2393 | * delay detach of session, but release pty, since | |
2394 | * the fd's to the child are already closed | |
2395 | */ | |
cdd66111 | 2396 | if (s->ttyfd != -1) |
3c0ef626 | 2397 | session_pty_cleanup(s); |
3c0ef626 | 2398 | return; |
2399 | } | |
2400 | /* detach by removing callback */ | |
2401 | channel_cancel_cleanup(s->chanid); | |
2c06c99b | 2402 | |
2403 | /* Close any X11 listeners associated with this session */ | |
2404 | if (s->x11_chanids != NULL) { | |
2405 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2406 | session_close_x11(s->x11_chanids[i]); | |
2407 | s->x11_chanids[i] = -1; | |
2408 | } | |
2409 | } | |
2410 | ||
3c0ef626 | 2411 | s->chanid = -1; |
2412 | session_close(s); | |
2413 | } | |
2414 | ||
2415 | void | |
700318f3 | 2416 | session_destroy_all(void (*closefunc)(Session *)) |
3c0ef626 | 2417 | { |
2418 | int i; | |
e9a17296 | 2419 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2420 | Session *s = &sessions[i]; |
700318f3 | 2421 | if (s->used) { |
2422 | if (closefunc != NULL) | |
2423 | closefunc(s); | |
2424 | else | |
2425 | session_close(s); | |
2426 | } | |
3c0ef626 | 2427 | } |
2428 | } | |
2429 | ||
2430 | static char * | |
2431 | session_tty_list(void) | |
2432 | { | |
2433 | static char buf[1024]; | |
2434 | int i; | |
6a9b3198 | 2435 | char *cp; |
2436 | ||
3c0ef626 | 2437 | buf[0] = '\0'; |
e9a17296 | 2438 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2439 | Session *s = &sessions[i]; |
2440 | if (s->used && s->ttyfd != -1) { | |
cdd66111 | 2441 | |
6a9b3198 | 2442 | if (strncmp(s->tty, "/dev/", 5) != 0) { |
2443 | cp = strrchr(s->tty, '/'); | |
2444 | cp = (cp == NULL) ? s->tty : cp + 1; | |
2445 | } else | |
2446 | cp = s->tty + 5; | |
cdd66111 | 2447 | |
3c0ef626 | 2448 | if (buf[0] != '\0') |
2449 | strlcat(buf, ",", sizeof buf); | |
6a9b3198 | 2450 | strlcat(buf, cp, sizeof buf); |
3c0ef626 | 2451 | } |
2452 | } | |
2453 | if (buf[0] == '\0') | |
2454 | strlcpy(buf, "notty", sizeof buf); | |
2455 | return buf; | |
2456 | } | |
2457 | ||
2458 | void | |
2459 | session_proctitle(Session *s) | |
2460 | { | |
2461 | if (s->pw == NULL) | |
2462 | error("no user for session %d", s->self); | |
2463 | else | |
2464 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2465 | } | |
2466 | ||
2467 | int | |
2468 | session_setup_x11fwd(Session *s) | |
2469 | { | |
2470 | struct stat st; | |
e9a17296 | 2471 | char display[512], auth_display[512]; |
2472 | char hostname[MAXHOSTNAMELEN]; | |
665a873d | 2473 | u_int i; |
3c0ef626 | 2474 | |
2475 | if (no_x11_forwarding_flag) { | |
2476 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2477 | return 0; | |
2478 | } | |
2479 | if (!options.x11_forwarding) { | |
2480 | debug("X11 forwarding disabled in server configuration file."); | |
2481 | return 0; | |
2482 | } | |
2483 | if (!options.xauth_location || | |
2484 | (stat(options.xauth_location, &st) == -1)) { | |
2485 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2486 | return 0; | |
2487 | } | |
2488 | if (options.use_login) { | |
2489 | packet_send_debug("X11 forwarding disabled; " | |
2490 | "not compatible with UseLogin=yes."); | |
2491 | return 0; | |
2492 | } | |
2493 | if (s->display != NULL) { | |
2494 | debug("X11 display already set."); | |
2495 | return 0; | |
2496 | } | |
680cee3b | 2497 | if (x11_create_display_inet(options.x11_display_offset, |
2498 | options.x11_use_localhost, s->single_connection, | |
665a873d | 2499 | &s->display_number, &s->x11_chanids) == -1) { |
3c0ef626 | 2500 | debug("x11_create_display_inet failed."); |
2501 | return 0; | |
2502 | } | |
665a873d | 2503 | for (i = 0; s->x11_chanids[i] != -1; i++) { |
2504 | channel_register_cleanup(s->x11_chanids[i], | |
2c06c99b | 2505 | session_close_single_x11, 0); |
665a873d | 2506 | } |
e9a17296 | 2507 | |
2508 | /* Set up a suitable value for the DISPLAY variable. */ | |
2509 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2510 | fatal("gethostname: %.100s", strerror(errno)); | |
2511 | /* | |
2512 | * auth_display must be used as the displayname when the | |
2513 | * authorization entry is added with xauth(1). This will be | |
2514 | * different than the DISPLAY string for localhost displays. | |
2515 | */ | |
2516 | if (options.x11_use_localhost) { | |
680cee3b | 2517 | snprintf(display, sizeof display, "localhost:%u.%u", |
e9a17296 | 2518 | s->display_number, s->screen); |
680cee3b | 2519 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", |
e9a17296 | 2520 | s->display_number, s->screen); |
2521 | s->display = xstrdup(display); | |
2522 | s->auth_display = xstrdup(auth_display); | |
2523 | } else { | |
2524 | #ifdef IPADDR_IN_DISPLAY | |
2525 | struct hostent *he; | |
2526 | struct in_addr my_addr; | |
2527 | ||
2528 | he = gethostbyname(hostname); | |
2529 | if (he == NULL) { | |
2530 | error("Can't get IP address for X11 DISPLAY."); | |
2531 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2532 | return 0; | |
2533 | } | |
2534 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
680cee3b | 2535 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), |
e9a17296 | 2536 | s->display_number, s->screen); |
2537 | #else | |
680cee3b | 2538 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, |
e9a17296 | 2539 | s->display_number, s->screen); |
2540 | #endif | |
2541 | s->display = xstrdup(display); | |
2542 | s->auth_display = xstrdup(display); | |
2543 | } | |
2544 | ||
3c0ef626 | 2545 | return 1; |
2546 | } | |
2547 | ||
2548 | static void | |
2549 | do_authenticated2(Authctxt *authctxt) | |
2550 | { | |
2551 | server_loop2(authctxt); | |
cdd66111 | 2552 | } |
2553 | ||
2554 | void | |
2555 | do_cleanup(Authctxt *authctxt) | |
2556 | { | |
2557 | static int called = 0; | |
2558 | ||
2559 | debug("do_cleanup"); | |
2560 | ||
2561 | /* no cleanup if we're in the child for login shell */ | |
2562 | if (is_child) | |
2563 | return; | |
2564 | ||
2565 | /* avoid double cleanup */ | |
2566 | if (called) | |
2567 | return; | |
2568 | called = 1; | |
2569 | ||
d4487008 | 2570 | if (authctxt == NULL) |
cdd66111 | 2571 | return; |
d4487008 | 2572 | |
2573 | #ifdef USE_PAM | |
2574 | if (options.use_pam) { | |
2575 | sshpam_cleanup(); | |
2576 | sshpam_thread_cleanup(); | |
2577 | } | |
2578 | #endif | |
2579 | ||
2580 | if (!authctxt->authenticated) | |
2581 | return; | |
2582 | ||
cdd66111 | 2583 | #ifdef KRB5 |
2584 | if (options.kerberos_ticket_cleanup && | |
2585 | authctxt->krb5_ctx) | |
2586 | krb5_cleanup_proc(authctxt); | |
0fff78ff | 2587 | #endif |
cdd66111 | 2588 | |
2589 | #ifdef GSSAPI | |
2590 | if (compat20 && options.gss_cleanup_creds) | |
2591 | ssh_gssapi_cleanup_creds(); | |
2592 | #endif | |
2593 | ||
cdd66111 | 2594 | /* remove agent socket */ |
2595 | auth_sock_cleanup_proc(authctxt->pw); | |
2596 | ||
2597 | /* | |
2598 | * Cleanup ptys/utmp only if privsep is disabled, | |
2599 | * or if running in monitor. | |
2600 | */ | |
2601 | if (!use_privsep || mm_is_monitor()) | |
2602 | session_destroy_all(session_pty_cleanup2); | |
3c0ef626 | 2603 | } |